A man and two women sustained injuries caused by a sharp item in the Cote-des-Neiges-NDG, on Sunday, long Goyer Street.
Police suspect the stabbing incident to be a case of domestic violence.
A female, aged 39, previously in critical condition, is now stable. The other two are out of danger.
A male suspect was taken into custody and rushed to hospital for non-life threatening injuries.
Police was alerted to the disturbance at around 3 p.m.
They established a perimeter to ease information gathering regarding the attack. It is not clear what object was involved in the attack.