Canadian police say at least four people, including two police officers, have been killed in a shooting in Fredericton, New Brunswick, in the east of the country. The suspect is in custody.

Fredericton Police said they responded to the incident in the Brookside Drive area of the city at about 7:30 a.m. local time Friday. The circumstances of the shooting weren't immediately clear.

Police have not released the names of the two Fredericton officers and two other victims who were killed.

"Please appreciate this is a difficult time for their families and our colleagues," police tweeted.

During the incident, officers urged the public to avoid the area and stay in their homes, keeping their doors locked. Police later confirmed there was no further threat to the public.

After announcing that the suspect - who has not been identified - is in custody, police tweeted that the Brookside area would be "contained for the foreseeable future" because the investigation is ongoing.

Robert DiDiodato, who lives near the scene of the incident, said he heard a series of "firecracker" noises at about 7 a:m., CBC reported.

"With the tempo, it might've been a gunshot. It was sort of like a pop, pop, pop, pop," he said.

He said he heard similar sounds about five minutes later. "Doors are locked and everybody's inside," he said, according to CBC.

Fredericton, the capital of in New Brunswick province, has a population of about 60,000.