A gunman opened fire in a movie theater in the US state of Louisiana on Thursday, shooting dead two people and wounding seven others before killing himself, police said.

The shooter was described as a white male in his 50s and he appeared to have died from a self-inflicted wound, local police said in a press conference.

Witnesses said the shooting took place at the Grand 16 theater in the city of Lafayette during a showing of the film "Trainwreck".

It comes as a jury deliberates the death penalty for the gunman in a 2012 theater massacre in Colorado that left 12 dead and 70 injured.

Ambulance crews rushed the injured to hospital, Clay Henry from the Acadian Ambulance service told CNN.

Television images showed a hectic scene at the cinema, surrounded by dozens of emergency cars and crews.

"Prayers for Lafayette at Grand Theater. Talking to state police colonel about shooting in Lafayette," tweeted state governor and US presidential candidate Bobby Jindal, who spoke in support of victims and police at a press conference near the scene.