Actors with Crime Stoppers re-enact how Keni Su'a was beaten after he was shot in front of the Bolsa Vietnamese Restaurant on New Year's Day in Calgary. (CBC)

An innocent man who tried to flee a New Year's Day gang shooting in a Calgary restaurant was shot and beaten by his attackers before he died, police revealed on Tuesday.

In an attempt to generate tips in the case, Crime Stoppers taped a re-enactment of the Jan. 1 attack that killed three men, including Sanjeev Man, 22, a known gang member, and Aaron Bendle, 21, who police described as an "associate" of Mann.

The third victim, Keni Su'a, 43, had been eating in the Bolsa Vietnamese Restaurant when three men entered and opened fire. Su'a tried to escape but was gunned down in the parking lot.

The Crime Stoppers taping shows the attackers shooting Su'a and then beating him, information that previously had not been released by police.

"He was beaten and so it shows the mindset of the people that went after him," said Staff Sgt. Patty McCallum. "They tracked him down and they killed him.

"They purposely went after him and they could have let him go but they didn't."

Three people were shot dead, including Keni Su'a, a bystander who tried to flee, in what police say was a gang-related attack on New Year's Day at this Calgary restaurant. (CBC)

Investigators believe the gunmen went after Su'a because he was a witness to the shootings inside the restaurant at Macleod Trail and 94th Street S.E.

"We are going to be hindered by those people who are reluctant to come forth to police with information, those who are closer to the offenders. That's going to be a challenge we face regardless," said McCallum, acknowledging the difficulties that come with any gang-related homicide investigation.

Police hope the Crime Stoppers re-enactment will trigger the memory of other witnesses who might have been in the area and have information, she said.

Police are not releasing details of what happened inside the restaurant for investigative reasons, she added.

Last week, police said they're seeking two silver vehicles — a newer-model Mazda 3 car and a newer-model four-door Toyota truck — that were seen in the area of the fatal shootings on Jan. 1.