Montreal police have arrested a third teenager in the brutal beating of a 67-year-old woman in Montreal North.

The 15-year-old was picked up in Montreal on Monday evening, several hours after two other suspects were nabbed in the attack that rattled nerves in Montreal North.

Police fear for the woman's life after she was punched repeatedly in the head late Sunday night on Henri Bourassa near St. Vital.  The suspects are to appear in youth court on charges of attempted murder, but those charges could be upgraded if the woman dies.

Incident

The woman was on a bus when she got off at a stop at midnight.  She was quickly surrounded by the three suspects.

Police do not believe the boys had a weapon.  They punched the woman in the head several times. She is in hospital in critical condition with multiple head injuries.  A bystander called 911, which led police to arrest two of the suspects, aged 15 and 16, on Monday morning.

Lafreniere said police aren't sure why the woman was there at the time, but that she did live in the area.  He was also unsure if there was a secondary motive for the attack.

"It would be so easy to say it could be drugs, it could be street gangs," he said. "It's always easier for society to believe it's something else like that. It could be anything. We've got no clue at this moment that's why we're trying to figure out the motive of that. I'm very happy to see that bystander had decided to contact 911."