NEW YORK – Richard Matt, one of the two killers who escaped an upstate New York prison three weeks ago, was shot Friday, two sources told NBC News.

His condition was not immediately known.

Matt and David Sweat have confounded authorities since June 6, when they were reported missing after sawing through the walls of their cells, shimmying through the works of the building and popping out of a nearby manhole to freedom.

A prison seamstress, Joyce Mitchell, has been charged with helping the two escape. This week authorities charged a second prison worker, Gene Palmer.

News of the shooting came hours after a New York State Police official told reporters that the killers might have headed for Canada.