MONTREAL -- Police were still finding shells on a Little Burgundy street on Sunday afternoon, more than 12 hours after a gun battle ended with three people shot, including a 13-year-old.

Investigators say they believe it all started during a music-video shoot that devolved into violence.

“What we know for now is that probably there was two groups of people [who] came for a sort of video or a film that they were making in the area here,” said Benoit Boisselle of Montreal police.

Police believe a “verbal fight” began, and after that things spiralled out of control and gunshots were fired, he said. The 911 calls were made at around 10:50 p.m.

First responders found a 25-year-old man on St. Martin St. with gunshot wounds. Later, a 13-year-old boy arrived at the hospital shot in the leg. Several hours later a third person, a 31-year-old man, also sought medical attention for a gunshot wound to his leg.

Police said the victims weren’t “collaborating” much with them, so it wasn’t easy to piece together what had happened.

“It’s going to be a long way to understand what happened exactly,” said Boisselle.

People in the neighbourhood on Sunday were also reluctant to talk about what happened. But one relative of the 13-year-old victim told CTV News that the boy lives nearby and was just in the wrong place at the wrong time.

That family and others said they don’t want to speak publicly about what happened for their own safety.

At least two guns were used in the shoot-out. Bullets were scattered across at least two blocks on Terr. Coursol between Des Seigneurs and St. Martin.

If police continue to get very little information from witnesses and from the skittish victims, they’ll be relying on whatever surveillance footage they can find from the area, they said.