Police searched into the night for two armed men following a daytime shooting in St. Catharines, Ont., on Thursday that sent three people to hospital, two of them in life-threatening condition.

Niagara regional police said officers were looking at a number of residences in a downtown area of the city south of Toronto in what they described as a “slow, methodical process.”

Const. Phil Gavin said late Thursday that officers were still looking for two men between the ages of 19 and 23 who were wearing hoodies and jeans.

“Our detectives will be continuing the investigation overnight,” Gavin wrote in a series of tweets just before midnight. “The suspects remain outstanding.”

In a statement issued early Friday, Niagara police said they were holding one scene overnight for forensic examination.

Earlier in the evening, Gavin told a news conference “the full strength of the Niagara regional police” was involved in the investigation.

“We’re doing everything we can to resolve this situation safely for everyone involved,” he said, adding investigators believe the shooting was a targeted incident.

Those injured in the shooting have not been publicly identified, but authorities said two were flown to trauma centres in life-threatening condition, while a third was taken to a local hospital with non-life-threatening injuries.

Gavin said police were called to the intersection of Church and Niagara streets at around 3:45 p.m. The nearby intersection of Queenston and Geneva streets was also affected, he said.

Gavin said numerous officers, including the tactical unit, negotiators, the K-9 unit and emergency responders were all on the scene.

At various points throughout the evening, officers with the force’s emergency task unit walked in and out of a building on the mostly residential street where the shooting took place, guns drawn and shields raised.

Several civilians could also be seen leaving the building with their hands up.

Police advised residents to stay out of the area, and employees of local businesses said they remained inside with doors locked until more information was available.

More than a dozen people who live within the police line waited well into the night before they were allowed to return home shortly before midnight.

Some approached officers guarding the police tape, demanding to be let through. Others, whose properties fall just outside the line, sat on their porches to watch the action unfold.

Dan Peterson, who’s lived in the area for more than a year, was among those waiting outside police lines. He was turned away from the police tape at 5 p.m. and was still waiting to be allowed through four hours later.

“We’re just waiting the situation out,” he said, noting that others had tried to dart through the police tape.

Peterson said that while the neighbourhood isn’t crime-free, he was surprised by the magnitude of the violence.

“You see little scraps here and there, but that’s about it,” he said. “That’s child’s play compared to what’s going on now.”

Coun. Mat Siscoe, who represents part of the area where the shooting took place, said the neighbourhood has struggled economically in recent years.

“The main hospital used to be just down the street from there, and it’s been a fairly economically depressed area since the hospital closed down about four years ago,” he said.

But he said such levels of violence are unusual in the neighbourhood.

“It’s unusual for the city of St. Catharines in general,” he said. “We’re not used to gun violence in the city. Not on this scale.”