Winnipeg police have arrested two teens and are on the lookout for two others after a stabbing on a Winnipeg Transit bus over the weekend.

Police put out a call for witnesses Tuesday after a 27-year-old man was stabbed on a bus at about 6 p.m. Sunday in the area of Stradbrook Avenue and Harkness Avenue. Four youth allegedly stabbed and pepper sprayed him in what police described as an "unprovoked attack."

Police arrested two males, age 16 and 14, Tuesday night just before 9 p.m. on Magnus Avenue near Lawrence Street in the Inkster East neighbourhood. Police also arrested a 38-year-old man who was with the teens at the time.

Investigators believe the trio assaulted a 16-year-old male with a knife and bear spray on Tuesday near Selkirk Avenue and Salter Street. The teen's injuries were non-life-threatening.

The two teen suspects and 38 year old were charged with aggravated assault and possession of weapons.

Two unidentified male youths are still wanted in connection with the bus stabbing.

Anyone with information that could help the investigation is asked to call police at 204-986-2877 or Crime Stoppers at 204-786-8477.