04/08/2015 06:48 EDT | Updated 06/08/2015 05:59 EDT

Man stabbed to death inside Montreal North apartment

Police arrested a 21-year-old man on Tuesday night in connection with a homicide at a Montreal North duplex.

A 51-year-old man was stabbed to death inside an apartment on Pigeon Avenue. 

Police were called to the scene around 8:30 p.m. Tuesday. 

They found the younger man on site. He had also been stabbed. 

He was arrested and transported to hospital, where he is under police surveillance.

​Investigators will speak to the man as soon as his condition permits them to. 

Police do know that the victim and the alleged killer knew each other.

This is Montreal's ninth homicide of 2015.