One of the most basic and dangerous jobs for police is conducting searches for hidden suspects. And perhaps the most dangerous search of all is the search of confined spaces such as tunnels, caves, sewers, crawl spaces, attics, basements, closets, and under and inside objects. Suspects can and do hide anywhere they can fit, which can be in the smallest spaces imaginable.

What makes confined space searches so dangerous is that they are essentially “ambushes” waiting to happen. Suspects in confined spaces are in “fight or flight” mode, which makes them as unpredictable and dangerous as any cornered animal.

Confined spaces usually have only one way in or out, little or no maneuvering room, and poor or no lighting. Additional dangers include creatures such as rats, spiders, and/or snakes. You also may face hazards such as broken glass, human or animal waste, sewage, and/or sharp objects. The combination of dangers presented by the cornered suspect and by other hazards makes confined spaces the most dangerous search environment imaginable.

Tunnel Rats
Officers who are assigned to go into confined spaces and confront hidden suspects are often called “tunnel rats,” a term borrowed from the Vietnam War when smaller stature soldiers and Marines were sent into Viet Cong tunnels to flush out the enemy or do battle with a GI .45.

It takes the right person to be a tunnel rat. You have to be physically and mentally fit, agile, small in stature, and non-claustrophobic. You also have to be willing to tackle the rigors and dangers of going into confined spaces alone, capable of dealing with the hidden suspect, and/or other unknown dangers. Just as breachers and door men are a special breed, so are tunnel rats. 

Pick the right person for the job, and the job will get done correctly every time. Pick the wrong person for the job, and one day a hidden suspect will be “missed” (not found). And remember, not all “small” police officers are tunnel rat material.

The tunnel rat is a very important resource for a tactical unit. This is true even though you have a variety of tools and resources to deal with suspects in confined spaces. You can send in K-9s, chemical agents, and/or distraction devices. You may also have access to tactical pole cameras, through-the-wall-radar, and other high-tech tools. Yet the most common way to search confined spaces continues to be the officer who is designated as a tunnel rat. This is understandable, since the vast majority of confined space searches do not involve enough probable cause to employ dogs and gas. I’m not going to debate which tactic is better because every team has its own preference. Bottom line is whatever you think is best for you is what you’ll end up going with.

Still, when faced with a suspect in a confined space, odds are somebody has to go in. As retired Cleveland Police SWAT Sgt. Tom Horan often said, “Eventually someone has to stick their tomato (head) into the confined space to make sure no one is inside.”

That someone is usually a tunnel rat. And the more tunneling you do, the better you become. 

Very often tunnelers get their first taste as rookies. That was my experience. At in-progress scenes, veteran cops boosted me through windows, so I could find and open doors for them. In essence, this meant searching locations alone and at times encountering suspects while opening doors for other cops. After a while I started to develop a search sixth sense.

Many SWAT teams designate the position of tunnel rat as a specialty. Make sure that your “rat” has the right skills to do the job, otherwise, you’re chancing missing some hidden suspect.
Many years ago, my team missed a hidden, barricaded suspect and ended up dealing with him the next day, this time arresting him. The debrief revealed that the original searchers overlooked the suspect’s hiding place because “nothing appeared disturbed.” After that, our ironclad rule was always to physically search every inch of a location and then double-check using different searchers. Bottom line is you can’t afford to “miss” any suspects. We were lucky, but we learned from it and corrected the problem.

Searching a Building
Regardless of what region of the country you’re from, buildings are essentially the same. However, your local architecture will be unique to your specific area. Some regions have basements and cellars, while others have crawl spaces. What’s important is to thoroughly familiarize yourself with your area’s specific building styles and designs, paying particular attention to the confined spaces.

There are few books on the subject of building searches, and even fewer on confined space searching; however, the book I highly recommend is “Building Search: Tactics for Patrol Officers” by Capt. James Stalnaker of the San Bernadino (California) Sheriff’s Department. This book should be required reading for all police searchers because it’s filled with common-sense tips, techniques, and tactics.

Search Tips
When it comes to confined space searches, the basics still apply, but you have to adapt your tactics to the unique challenges confined spaces present. I know of no textbook that covers confined space searches for police. However, if we were able to pick the brains of a roomful of tunnel rats, this is what we’d likely learn from their collective experiences:

• Develop your own search rituals, tactics, and techniques. By ritual, I mean sizing up the confined space, communicating with cover and backup officer(s), and making a mental plan for ingress or egress.

• Have an “Oh shit!” plan. Murphy lives in confined spaces.

• Slow down. Do some tactical breathing. Stop. Look. Listen. Smell (sniff). Use ALL of your senses before you go into any confined space, including your “sixth sense.”

• Carry only the essential equipment, nothing bulky that will catch on anything. A recommended list would include: two pistols in secure holsters, two lights (flashlight(s) or gun-mounted lights with batteries fully charged), a TASER, personal body armor, tactical shooting gloves, knee and elbow pads, QuikClot bandage, portable radio (muted), gas mask, polycarbonate non-fog eyewear, and ballistic helmet but only if it allows you to look up, down, and to the side. You must be totally self-contained, especially if you’re the lone searcher.

• Don’t wear or carry anything that will catch on protruding nails, make noise, or otherwise interfere with your searching ability.

• In sewers, you will likely wear a SCBA, which means you need prior training, fitting, etc. On scene on-the-job training is not the best time to learn about SCBAs.

• Train to search confined spaces before you have to do it in real life. Make sure that the training conditions are realistic so that you can learn what works, what doesn’t, and that includes your weapons and equipment. That said, my guess is that many if not most tunnel rats rarely receive formal tunnel training and instead learn through OJT.

Search Tactics and Techniques
• First, make certain your backup is ready. If you encounter a problem requiring immediate assistance, the last thing you want or need is delay caused because your backup isn’t ready. Make sure you talk over your search plan with your backup.

• Before entering any confined space, deploy whatever specialty equipment you have to assist you. Technology advances include handheld throwable 360-degree remote low-light/IR cameras capable of locating a hiding suspect.

• Consider verbally ordering the suspects to come out with their hands in plain view. K-9s can also be used to make “announcements,” advising suspects that it’s better to give up now.

• Depending on the gravity of the situation, you should consider chemical agents. However, think twice about it because you will be forced to work wearing a gas mask that will restrict your breathing and vision. Plus, if anything happens to break the mask’s seal, you’ll be gassed and trapped in a confined space. Personally, I prefer a non-gas environment. But it’s an individual choice, and the tunnel rat must have a say in it.

• Only enter a confined space when you are ready. After all, it’s your “tomato” that will be entering into the “unknown” with the very real probability that you will “disappear” completely from your backup’s view almost immediately after you’re inside the confined space.

• Take the time to acclimate to your surroundings and allow your eyes to adjust to the transition to the dark (preferably prior to entering any confined space). You’ll need to make sure your “360-degree” view is clear of danger, and you will most likely need to use your flashlight.

• When working with light, work from behind a “wall of light” but remember that, if the suspect shoots at the light, he’s also shooting directly at your head. This is especially true if the crawl space is so low it forces you to “low crawl.” This is where your decision of whether or not to wear your ballistic helmet becomes crucial. On one hand, helmets protect your head. On the other hand, helmets restrict full visibility and maneuverability. Your decision has to be made prior to an actual search, preferably in training.

• Search methodically and systematically. Stop. Look. Listen. Smell. And use your sixth sense periodically.

• Searching confined spaces is physically and mentally exhausting work, so take frequent timeouts. And do your tactical breathing to calm yourself down (as needed). Remember, there are no time constraints. So take all the time you need.

• Continually assess your situation and, if you haven’t already done so, have your backup enter the confined space along with you, even if it’s only to watch your back or cover where you’ve already searched. If your backup also enters the confined space, another “up top” backup needs to take his place. Preferably two, since they’re the ones who will make the rescues (if needed).

• Alternate searching with your light with physically searching and assess as you go. Always remember the way you came in because many confined spaces (especially crawl spaces) have only one way in/way out and you most likely won’t be able to see it from your low-crawl, flat on your belly, front-facing position. Even the most “non-claustrophobic” experienced searcher is susceptible to claustrophobia if escape access is totally cut off.

• When it comes to confined space searches, always remember you are dealing with two challenges simultaneously: the suspect(s) and the confined space itself. Which gives you all the more reason to have backup as close as practical. There is a very real possibility even probability that the suspect(s) will physically fight you, resist by locking legs or arms onto pipes, beams, etc., and/or employ a weapon against you. For that reason, the strong recommendation is to conduct the search with pistol in hand finger outside the trigger guard.

• In a confined space, ground fighting takes on a whole new meaning. Fighting and/or shooting from a prone, kneeling, crawling position in darkness against a hidden, desperate adversary by yourself until your backup can reach you requires skill and a fierce determination to win.

• If you can’t locate formal confined space training, you need to develop your own tunnel training that incorporates shooting with ground fighting techniques both with and without impact weapons.

• One technique that works well is to shine a high-intensity flashlight directly into the eyes of a suspect, momentarily blinding him and giving you the tactical advantage. I prefer a full-size rechargeable Streamlight, which can double as an effective impact weapon if necessary. While these lights have gotten a bad rap by some critics, they have a proven track record of success when properly deployed. Check with your agency regarding the rules for “heavy” flashlights.

• Work out a simple hand signal system. A nod works well.

• Closets and the areas under furniture are also confined spaces. Develop effective, proven tactics/techniques to clear them. Usually, only one searcher can fit into a closet, which may be filled with clothes, boxes, and bags. Every closet must be thoroughly searched for hidden suspects. Also, don’t forget to look up, down, and inside every conceivable space. Countless bad guys have been found hiding in or under the smallest, most inconceivable places, including hanging from closet clothes bars, inside box springs, even inside appliances like refrigerators and clothes washers. Thoroughly search everything. And remember, bullets penetrate doors, walls, and furniture.

• Before you can say a location or premise is “secure,” have a different search team thoroughly search the entire location again. Yes, this takes extra time; however, we can’t afford to miss any suspects, in the mistaken belief the premises is secure. The few extra minutes spent on a second search is well worth the effort.

• For searches that take more time than normal—especially inside what I call “battleships” with numerous hiding places and/or during inclement weather—a good idea is for the search team leader to make periodic broadcasts, informing perimeter personnel to “continue holding because the location is not secure yet. Once the location is considered completely secure, the team leader should confirm this with every search team member before announcing that it is “clear.”

Don’t Be in a Hurry
The bottom line regarding searching confined spaces is that they require special search tactics and techniques, preferably performed by experienced tunnel rats. Many SWAT raid teams prefer dynamic entries and pride themselves on how fast they can clear a target location. Speed is important but, when it comes to checking confined spaces, searchers need to slow down. No target can be considered secure until the entire location has been thoroughly searched and searched again. This takes time and patience.

Throughout my career, especially in SWAT, I was privileged to be able to tunnel countless times, arresting many a suspect, hidden in some crawl space, basement, attic, or closet. For all the countless searches I participated in during my career, the ones that stand out the most are the (rare) times suspects were missed during the initial search. Like the suspect who fired 20-plus rounds with his sawed-off rifle at police then hid in a six-story abandoned warehouse. Numerous officers searched the entire building for hours, without success, declared the building secure and left the scene.  An hour later, the suspect emerged from the “secure” building and was apprehended by a lone perimeter car, waiting patiently, just in case. The suspect cooperated and showed the arresting officers where he had hidden in the building. He was deep inside a sub-basement in a large, empty room, proned out, rifle aimed at the doorway.

Officers searched the room he was hiding in but never went in far enough to encounter him. These officers were lucky because had they gone only a little further into the room, the suspect intended to shoot them down with his rifle.

A target location is never secure until it is 100-percent secure. In this case, only luck prevented a tragedy from occurring.

I’m sure most you have your own “horror stories” of “misses and near misses.” We can and sometimes do make mistakes. The main thing is to learn from them and make sure they never happen again.


Robert O'Brien
Robert O'Brien

Robert O'Brien

A member of the TREXPO Advisory Board, Sgt. Robert "Bob" O'Brien Cleveland SWAT Ret. is the founder of the R.J. O'Brien Group Ltd., a law enforcement training and consulting service that advises and trains a number of local, state, and federal SWAT teams.

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A member of the TREXPO Advisory Board, Sgt. Robert "Bob" O'Brien Cleveland SWAT Ret. is the founder of the R.J. O'Brien Group Ltd., a law enforcement training and consulting service that advises and trains a number of local, state, and federal SWAT teams.

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