A manhunt is underway after a gunman fatally shot three RCMP officers and injured two others in Moncton, N.B.

As heavily armed police conduct their search, residents in the Moncton Coliseum area and Pinehurst subdivision are advised to remain under lock down.

"We are still urging the public to stay inside their homes," Const. Damien Theriault of the Codiac RCMP told CTV News Channel overnight.

Police are looking for a 24-year-old Moncton man, Justin Bourque. Police tweeted a photo of the suspect dressed in military camouflage and carrying guns.

Theriault confirmed Bourque is a person of interest in connection with the shootings, but cited operational concerns for not releasing any other information.

"He is believed to be armed and dangerous, and people should avoid contact with him," Theriault said.

A Facebook page under the same name had several anti-gun control messages. Lyrics from a Megadeth song, ending with "I believe my kingdom will come," were posted shortly before the shootings began Wednesday night.

The Horizon Health Network, New Brunswick's largest health authority, said two gunshot victims were admitted to Moncton Hospital.

"At this time I can confirm that we have received a total of two victims related to this tragedy," Dr. Dhany Charest, Moncton Hospital's chief of staff, said in a statement.

"They have been treated and are in stable condition in hospital. We have also received a third patient from a separate incident that occurred Wednesday evening. That person is in critical condition in the OR."

The hospital is restricting visits to those with critically ill family members.

Prayers and condolences

Moncton Mayor George LeBlanc offered his condolences for those affected by the "terrible tragedy."

"We as a city must pull together as a family to support those who have suffered losses," he said.

Prime Minister Stephen Harper offered his condolences too, as well as "prayers for the speedy recovery of those injured."

In a statement, Harper added that, "This violent incident is a stark reminder that our men and women in law enforcement put their lives on the line in Canada every day to protect our citizens and communities."

According to the RCMP Honour Roll page online, the last Mountie shot dead in the line of duty was Const. Douglas Scott. He died after responding to a call on Nov. 5, 2007.

In a statement, New Brunswick Premier David Alward said he was "shocked and saddened" to hear of the shooting.

"On behalf of all New Brunswickers, I would like to extend my thoughts and prayers to those affected. I would ask New Brunswickers, particularly in those areas identified by police, to follow the situation as it develops and to listen to the advice of police," he said.

Alward told CTV Atlantic that he has been in touch with the commander of Codiac RCMP and said the shooting has been "certainly devastating for their force."

Alward urged residents of Moncton to "maintain vigilance and listen to reliable sources for information."

Federal Public Safety Minister Steven Blaney tweeted late Wednesday that he was "shocked by the tragedy in Moncton," and said his thoughts and prayers are with frontline RCMP officers and their families.

With files from CTV News and The Canadian Press

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