Two police officers were among four people killed Friday in a shooting in eastern Canada and a suspect has been arrested, authorities said.

Residents of the Brookside neighborhood of Fredericton, New Brunswick reported waking to the sounds of multiple gunshots.

Witnesses described to the Canadian Broadcasting Corporation (CBC) seeing the barrel of a rifle or shotgun poking out from the window of a low-rise apartment building and firing into a courtyard, while the bodies of two officers lay on the ground nearby.

Heavily armed police, paramedics and firefighters quickly descended on the scene and a lockdown of the neighborhood was ordered, trapping some early risers in daycare facilities, coffee shops and other businesses.

Others were seen being escorted by police from their homes — some still in pyjamas — to safety beyond a police cordon.

Authorities in the provincial capital initially urged people in the Brookside neighborhood to stay indoors, describing an “active incident” on Twitter.

Around an hour after giving first word of the killings, a second and then a third message from police said: “At this time, we can confirm that we have one suspect in custody” and “of the four people killed in this morning s shootings on Brookside Drive, two were Fredericton police officers.”

Then came word that the threat had been neutralized, the lockdown was lifted and the police cordon was shrunk to a few blocks: “We can confirm that there is no further threat to the public, and lockdowns are not required at this time.”

Also, police added: “We can confirm that the suspect in custody is currently being treated for serious injuries related to this morning s shooting incident.”

The circumstances of the shooting in Fredericton, about 75 kilometers (45 miles) from the border between Canada and the US state of Maine, were not immediately clear.

The shooting happened in a sleepy residential area of the city north of downtown.