(Cover) - EN Showbiz - US President Barack Obama is "shocked and saddened" following the fatal shootings at a screening of The Dark Knight Rises.

A masked gunman named as 24-year-old James Holmes opened fire as the new Batman movie was screened at a theatre in Aurora, Colorado, at midnight today. At least 12 people are reported to have died with as many as 50 believed to include children and a baby injured.

Obama has released a statement in which he asks Americans to pull together during this sad time.

"Michelle [US First Lady] and I are shocked and saddened by the horrific and tragic shooting in Colorado," he said.

"We are committed to bringing whoever was responsible to justice, ensuring the safety of our people, and caring for those who have been wounded.

"As we do when confronted by moments of darkness and challenge, we must now come together as one American family."

It is understood that the man rose to his feet and brandished a gun when Batman first appeared on screen during the Christopher Nolan-directed release.

He is also thought to have thrown tear gas into the crowd and was wearing a gas mask and body armour with some outlets claiming he was dressed as Batman villain Bane.

The gunman was arrested in the parking lot of the cinema. Police later evacuated his apartment block after he made comments about explosives. Officers have confirmed he was carrying a handgun and a rifle, with claims he also had a shotgun. Contrary to earlier reports, it is thought he was acting alone.

Movie studio Warner Bros., which is behind The Dark Knight Rises, has also released a statement: "Warner Bros. is deeply saddened to learn about this shocking incident. We extend our sincere sympathies to the families and loved ones of the victims at this tragic time."

Tonight's Paris premiere for The Dark Knight Rises has been cancelled.

A host of stars have offered their support to those affected by the events.

"My heart goes out to all the people affected in the Aurora, CO shooting. May God be with that town and their families (sic)," Eva Longoria wrote on Twitter.

Billy Ray Cyrus, Mark Ballas and Lisa Rinna have also spoken about the incident. (C) Cover Media