VIDEO: 2 helicopters collide at Pasadena Police Department heliport

PASADENA, Calif. (KABC) -- A surveillance camera captured shocking footage of two helicopters colliding on the Pasadena Police Department's heliport.

In the November 2012 incident, one helicopter was flying in and another was getting ready to take off. That's when the rotor blades of one chopper collided with those of another.

Police say six people were injured -- including five officers on the helicopters and a civilian on the heliport pad. They were all treated at hospitals for minor injuries and released.

The footage was released recently by the National Transportation Safety Board.