The Vancouver Police Department is explaining the actions of its officers after video surfaced online of a dramatic takedown involving a Taser and a bean bag gun on the city's Downtown Eastside.

The nearly two-minute clip posted to Twitter by @stopdisplacement begins with a man lying on his back surrounded by several officers on the northeast corner of East Hastings Street and Dunlevy Avenue at around 11:30 a.m. on Tuesday.

Authorities can be heard instructing the man to roll over onto his stomach several times as more officers arrive at the scene.

The man does not follow the instructions at first, instead rolling several times towards a police car parked on Dunlevy before coming to a stop on his right side and then returning onto his back.

Al Fowler, who shot the video, said police had already deployed a Taser by that point, a detail the VPD confirmed to CTV News in an email statement.

The force told CTV staff at the nearby Patricia Hotel were concerned for their safety after a man entered the building and began acting aggressively, adding that the man was not a guest at the hotel but is known to staff "from a previous violent incident."

"When officers arrived, they encountered a man who was acting aggressively and appeared to be under the influence of drugs. He lunged at one of the officers and attempted to punch him. The officer was not harmed and was able to deploy his Taser. However, the Taser had little effect," police said.

That's when Fowler, who is the vice-president of the BC Association of People on Methadone, started recording.

"I see a cop car there, lights flashing and all of a sudden, 'bang,' I heard the Taser go off, so I drop my bicycle, I go running across the street then I finally had my phone recording," he told CTV. "They Tasered him twice and then they were yelling at him … You heard them telling him to 'Roll over. Roll over.'"

Between 1:22 and 1:37, three loud pops can be heard in the video.

Fowler said a bean bag gun was used during the takedown.

"The guy with the bean bag gun was like six, seven feet away from him," he said. "You know, that's like point blank range—and he shot him three times: 'Boom, boom, boom.'"

Police confirmed a bean bag gun was fired after the man failed to comply with officers' orders.

"The man was warned several times that a bean bag would be deployed if he remained non-complaint. Officers struck the man’s leg with several beanbag rounds, which proved enough distraction to allow the officers to move in and arrest him," the statement read.

According to Fowler, officers were eventually able to handcuff the man, who was then taken away in an ambulance.

'It was overkill': Fowler

Fowler, who also works with the Vancouver Area Network of Drug Users and the BC Centre for Substance Use, criticized the VPD for resorting to force without doing more to de-escalate the situation.

"They didn't have to make that big a deal about it," he said. "The guy's lying on the ground, on his back with his hands in the air. They should have the skills as police officers to arrest him without escalating the situation."

The advocate and researcher said witnessing the police's response makes him "angry about a lot of things."

"I don't know what he did wrong to get arrested … but I think it was overkill on that part."

Police confirmed a 35-year-old man from Surrey was taken to hospital "for an assessment related to drug impairment and the deployment of the Taser and bean bags," adding that charges related to assaulting an officer are anticipated.