VIDEO: Guard Killed in Marijuana Dispensary Burglary

An investigation was underway Tuesday morning after a security guard was shot and killed during an attempted robbery of an illegally operated medical marijuana dispensary in San Bernardino, Calif., the previous night, authorities said, reports KTLA .

Officers responded to the 2800 block of Rialto Avenue after someone reported that shots had been fired inside the dispensary, a news release from the San Bernardino Police Department stated.

Two armed men had entered the business around 10 p.m. Monday night and attempted to rob the dispensary, officials said in the release. One of the men forced his way into a back room and started shooting at the security guard, who returned fire, the release stated.

The victim was struck at least once in the gun battle and was pronounced dead at the scene. He was later identified by police as 25-year-old Anthony Victor Pineda of Rowland Heights.

Investigators said one of the men had been shot and police believed the man may have been critically injured. It was not immediately known if the two suspects got away with any cash or drugs from the medicinal pot dispensary.

According to San Bernardino police Lt. Rich Lawhead, people inside the business who described themselves as "volunteers" were originally uncooperative with the investigation, and that officers had to force entry into the dispensary. Authorities said that these types of pot shops are illegal in the city.