Witnesses say the shooter came in through the exit door at the front of the theater wearing all black, including a gas mask and bullet proof vest, and threw two tear gas canisters into the crowd (Hat tip - Duane Lester).

And when they started coughing, he opened fire:

re during an early Friday morning screening of the new Batman movie at an Aurora, Colorado, theater, Police Chief Dan Oates told reporters.

rmed suspect, who was wearing a bulletproof vest, was apprehended by police in a rear parking lot of the theater, Frank Fania, a police spokesman, told CNN. The suspect was not immediately identified, though Fania said he was believed to be in his early 20s.

"He did not resist. He did not put up a fight," Fania said. Police seized a rifle and a handgun from the suspect, and another gun was found in the theater, he said.The youngest victim was just six years old. Federal law enforcement officials say the gunman used at least four guns -- an "AK type" rifle, a shotgun and two handguns.

Here's cell phone footage showing the resulting chaos:

Here's police scanner audio of the Aurora Colorado Shooting:

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