MONTREAL -- A Montreal firefighter was injured while battling a four-alarm building fire in the Mercier-Hochelaga-Maisonneuve borough.

The Montreal fire department (SIM) said emergency responders were called to a fire in a three-storey building at 9:45 a.m. on Ontario St. East near Leclcaire St.

The SIM sent 31 vehicles and 105 firefighters to the scene.

SIM spokesperson William Murray said the fire started outside the building on a ground floor balcony and spread up to the roof.

"The cause of the fire is unknown," he said.

The building was evacuated and around seven families were cared for by the Red Cross on the cold Montreal day.

No civilians were injured, but one firefighter sustained minor injuries.

At 2 p.m., there was no fear of the fire spreading.

"The fire is under control but it's not fully extinguished," said Murray.