NEW YORK (PIX11) --- A correction officer at a Rikers Island jail facility was knocked out in an unprovoked attack on Wednesday afternoon, a union official said.

He was punched in the head at the Robert N. Davoren Center around 12:50 p.m., officials said. The correction officer's left eye was injured and medical workers were unable to remove his contact lens. He's also missing more than 10 teeth and suffered a laceration to the back of his head.