A shooting that left three men dead at a Calgary restaurant on New Year's Day was gang-related, police say.

Three assailants walked into the restaurant and opened fire on a table where two men and a woman were sitting, Calgary Deputy Police Chief Murray Stooke said.

The woman was unharmed, but a third man who was on his way to join them was also shot to death just outside the front door.

One of the three victims at the Bolsa Vietnamese restaurant was a known gang member, Stooke said, and it's likely the shooting was an escalation of violence between two rival gangs.

One of those killed was wearing a vest designed to protect him against bullets, the deputy chief also said.

The names and ages of the victims haven't been released.

The shootings came on the heels of Calgary's first homicide of the new year, the death of a man in his mid-20s early Thursday morning.

Police say they have charged a 32-year-old man with second-degree murder, while charges are being considered against another man.

The man who died, believed to be a newly arrived immigrant, was one of three injured people police found in front of a strip-mall pub on Whitefield Drive when they responded to a call about a fight around 1:30 a.m.

The man was rushed to hospital, where he later died, police said. They have not released his name.

With files from the Canadian Press