Cryan was a Bajoran male who served in the Bajoran Militia in the 24th century. He was assigned to Deep Space 9.
In 2376, Sergeant Cryan was assigned to watch over the Jem'Hadar Kitana'klan, who was being held in one of DS9's cargo bays, and was subsequently killed, along with corporal Devro, when the Jem'Hadar made a successful escape attempt, breaking Cryan's neck in the attack. (DS9 novel: Avatar, Book Two)