Security video footage of a vicious assault in the city’s downtown core shortly after midnight on New Year’s Day shows a man being punched in the head moments after ending up on the ground and slamming his head on the concrete sidewalk.

The video, which was obtained by CTV News Toronto, shows a man in a grey coat walking on the sidewalk near Queen and Bathurst streets around 12:30 a.m. The man is seen on the video lifting a garbage bag and running out of the frame as he swings it behind his back.

The man can then be seen running back into the frame while two people follow close behind him. A fight ensues and the group ends up on the street. At one point, the man in the grey coat can be seen being pushed up against a vehicle on the road.

A few seconds later, the three men end up on the sidewalk again. The victim can then be seen falling to the ground, slamming his head against the concrete. He is then punched in the head.

The two suspects flee while a group of people gather around the victim.

The circumstances leading up to the altercation are not known.

The victim has been identified by his employer as David Shellnutt. He is a lawyer in his 30s who has spent the last year working with Sher Law Professional Corporation, a Toronto-based firm specializing in employment, disability, and discrimination claims.

His employer, Hugh Sher, describes him as “a wonderful man” who has dedicated his life to social justice and helping those who were hurt or injured.

“I’m personally quite shocked. My staff is quite shocked. We are saddened for our friend. He is a tremendous man and we are hopeful he will be able to make a full recovery,” Sher told CTV News Toronto.

Shellnutt is a graduate Osgoode Hall Law School in Toronto, where he served as the head of the student council.

“David was a champion of the black social justice movement here in Toronto and his dedication to his social justice commitments are what made him a passionate, strong and powerful advocate,” he said. “All I can say right now is that we are deeply saddened by what’s happened. We are deeply saddened by the state he is in right now.”

Police said that when officers arrived at the scene, they found Shellnutt bleeding heavily. He was transported to a local hospital with a serious head injury, but his condition has since worsened.

Shellnutt’s injuries are now believed to be life-threatening.

“There tends to be, with any head injury, particularly when you have a significant element of bleeding and swelling, a period of time that needs to pass before you can determine what the level of function and the level of ability will be after the swelling and bleeding has subsided,” Sher said. “It’s pretty early in the stage right now. We are praying that he makes it through.”

“His commitment and compassion are what helped to fuel us every day and we will have to keep that up as he is recovering.”

Police have not released any descriptions of the suspects in the assault, but said that the men appear to have fled the area in a light blue car.

Investigators are urging anyone with information about the incident, or who may have video footage of the area, to contact police or reach out to Crime Stoppers anonymously.

With files from CTV News Toronto's Janice Golding