If you are in a residential neighborhood and you are being shot at by an unseen shooter, immediately turn left or right into a driveway and drive all the way up as far into the location as you can. If there are no driveways, drive over the curb toward the space between two houses. Immediately exit the police vehicle and try to locate the shooter.
At this point, breathe. Don't panic.
The last thing an officer should ever do is scream incoherently for help on the radio. This will only bring other officers into the kill zone, without any helpful information. Do request assistance or help, but ask responding officers to set up a large containment of the area until you can ascertain the suspect's location. If you know the direction the shots came from, have officers respond to your location from the opposite direction on foot via backyards or alleys. This is important: Have them stay off the street.
If you are being fired upon from the upper floor or the rooftop of a multi-story building, hit the accelerator and drive toward the building. This will reduce the angle of the kill zone because the shooter will have to reveal more and more of himself as he tries to keep the police car in his sights below his location. If necessary, drive the police car into the building’s lobby. In this situation, have responding officers take control of the rooftops of the adjoining buildings and contain the building where the suspect is located.
Unless the suspect presents an immediate threat to others, this situation should be handled by trained SWAT personnel. Officers should contain the area and begin to get intelligence information, building plans, etc., that will assist SWAT personnel with their mission.