CALGARY -- Charges have been laid for an unprovoked assault in downtown Calgary on New Year's Day, which police say is being investigated as a possible hate crime.

Police were called to a bus stop on Fifth Avenue near Second Street S.W. just after 7:30 a.m. on Jan. 1 after a man who was waiting there was assaulted by another man in an unprovoked attack.

A Calgary Transit bus driver saw the assault and called 911 before offering first aid to the victim.

The victim, a man in his 40s, was taken to hospital in serious but stable condition. Police say he has since been released.

Police arrested a suspect two blocks south of where the attack happened.

"The investigation has revealed the attack may be hate-motivated, and that the victim was targeted for his race," reads a release from police.

"It is believed this attack may be linked to several others similar in nature."

William Thomas Potter, 28, is charged with aggravated assault. He is scheduled to appear in court on Friday.

According to Sr. Const. Craig Collins, Potter is known to police. As a hate crime coordinator, Collins' job is to review all files that have a hate crime element to them. He said he will be reviewing other files Potter is believed to be involved in.

"The additional cases that were highlighted through the investigation of the street officers are that previous victims of an Asian descent have been targeted," he said.

"So with that, and a description, we are now looking at those cases on top of this original case."

Police have identified two particular cases of interest from 2019.

Anyone with information is asked to call the police non-emergency line at 403-266-1234 or Crime Stoppers at 1-800-222-8477.