The union representing Metrolink engineers is suing the Southern California rail authority to halt plans to activate video cameras in its commuter trains.

Metrolink said Tuesday the cameras are intended to increase safety after one of its passenger trains collided with a freight train in September 2008, killing 25 people. The engineer was text-messaging seconds before the crash.

The Brotherhood of Locomotive Engineers and Trainmen says the cameras are an invasion of privacy and has filed lawsuits in federal and Superior courts in Los Angeles.

Metrolink announced plans earlier this month to activate the in-cab video cameras. The union instead proposes a cell phone jamming system that blocks all incoming and outgoing cell phone calls and texts.