Police in Montgomery County are investigating the death of a man after police officers used a Taser to subdue him.

The 51-year-old man was unruly, so police first used pepper spray, then a Taser to subdue him. Once he was detained, he stopped breathing.

It is not clear whether the Taser played a role in his death, and the incident is under investigation. Police are working with the Office of the Chief Medical Examiner and interviewing roughly a dozen witnesses.

The incident started at 6:11 p.m. on Friday, when officers responded to a call about a man acting strangely in the 8800 block of Cross Country Place in Gaithersburg. Someone had called 911 saying the man was standing in a parked pickup truck yelling profanities, striking the truck with rocks and crawling on other vehicles.

When officers arrived they found the man laying in the bed of the truck. He then jumped to the roof of a neighboring SUV and continued to act aggressively. Officers instructed the man to stop, but when he failed to comply, they used pepper spray on him. He ran away but stopped on a nearby sidewalk.

The man started picking up potted plants and landscaping rocks and dropping them to the ground. He then walked over to the front door of 8830 Cross County Place, picked up a child's scooter that was outside and starting hitting the door with it. Officers asked the man to leave the porch of the home, but he declined.

More officers arrived, and when the man still wouldn't stop, two officers fired a Taser at him and restrained him with handcuffs.

Once he was cuffed, officers observed that the man was not breathing. They administered CPR was transported him to Shady Grove Hospital, where he was pronounced dead.

Police have not identified the man because they are still trying to contact family members, they said.

Five officers have been placed on administrative leave while the investigation into the man's death continues.