A 51-year old man is under arrested following a fatal stabbing in west-end Cartierville Saturday.
Police say it happened during an arguement between the suspect and his sister at a home on L'Acadie near Marcelin-Wilson.
"At a certain moment, the man grabbed a sharp object, stabbed the victim, 55-year old woman, in the upper body. During this aggression, the mother, 79-years old, was also wounded in the upper body. Both women were transported to the hospital", said police spokesman Daniel Lacoursiere.
The suspect's sister died Saturday night.
Authorities did not fear for the mother's life.
The reason for the arguement was not yet known.