An unruly passenger on a Frontier Airlines flight was tackled by fellow passengers Tuesday after they say he began punching an aircraft window.

Twenty minutes into the flight from Denver to Houston, witnesses say the man was punching the seat in front of him.

A passenger aboard a Frontier Airlines flight to Houston had a violent outburst on Wednesday after being asked to move, punching and kicking in his seat until he cracked one layer of the plane’s window mid-flight.