Calgary police are looking for a suspect after a man was shot at a downtown C-Train station last night.

Duty Insp. Paul Stacey said it happened just after 10 p.m. at an LRT platform at 6th St. and 7th Ave. S.W., just outside The Distillery.

Two men started arguing at the station, before one of the men shot the other in the chest, said Stacey.

The suspect then took off running along 7th Avenue S.W. and turned to run down 5th Street S.W.

The victim is believed to be in his early 30s, and remains in hospital in critical condition.

"It’s unknown why it occurred, there's no indication of any kind of argument or anything like that so we are just not sure of the motive at this point or if the victim and the offender knew each other, even."

Police are now reviewing closed circuit cameras along the LRT corridor and interviewing a number of witnesses.

The suspect is a white man, in his late 20s or early 30s. He's about 6’0" and was wearing a black fedora hat, black trench coat and black pants.