Washington, Jul 20 (IANS): At least 14 people were killed and 50 injured Friday in Denver at a cinema hall showing the new Batman movie "The Dark Knight Rises", a movie about a terrorist leader who overwhelms Gotham's finest.

Witnesses said the gunman wearing a gas mask opened fire and set off a type of smoke or tear gas bomb at the Century Theater in Aurora Mall outside Denver, reported Xinhua citing KUSA-TV.

Radio KOA said 30 to 40 people were injured and some may have been killed in the shooting.

As many as 20 people were being treated for gunshot wounds, three of them in serious condition, said CNN.

Police said the suspected gunman was in custody.

According to imdb, eight years on, a new terrorist leader, Bane, overwhelms Gotham's finest, and the Dark Knight resurfaces to protect a city that has branded him an enemy.

The movie has been directed by Christopher Nolan and it stars Christian Bale, Michael Caine and Gary Oldman.

Dan Oates, a police official, said: "Witnesses tell us he released some sort of canister. They heard a hissing sound and some gas emerged and the gunman opened fire."

"The shooting apparently went on for some time," BBC quoted him as saying.