Even after he left the theater, some people stayed behind not understanding what happened and thinking the movie might continue, Caldwell said. "I looked at them like, 'This is real. There's something wrong. We need to leave now.'"

Witnesses described the man as dressed in black and wearing a gas mask and bulletproof vest.

When the gunman began shooting, "I thought there was no way I was going to get out of there without getting shot," Freeman said.

In the rush to leave, some people were stepped on or pushed, Derek Poag told CNN.

Outside the theater, it was chaotic, with wounded people everywhere, Caldwell said. He saw one girl in a pink hoodie, her left side peppered with wounds.

Cell phone video taken outside the doors of the theater complex showed panicked moviegoers calling out for help or searching for friends.

One man can be seen walking out with assistance, the back of his shirt covered in blood. A woman examines her body, as if checking for wounds.

Donovan Tate said he saw a man crawling, a girl spitting up blood, and people with bullet holes in their backs. "There was this one guy who was stripped down to his boxers, it looked like he had been shot," perhaps in the back, Tate said. "It was crazy."

Alex Milano was in the next theater over that was also showing the Batman film.

He also said there was a shooting scene happening on screen when the sound of real bullets was heard nearby.

"Loud bangs came from the right of the theater. Smoke took over the entire theater, and it was really thick and no one could really see anything," he said.

Confused at first, Milano realized the severity of the incident when he saw "objects" starting to come through the wall, presumably bullets.

"I saw holes in the wall," he said.

Some people in his theater started moaning in pain, and alarms at the building started sounding.

Outside, Milano spoke with a woman who was inside Theater 9. What she heard "sounded like madness to me," he said.

One scene stuck in his head -- a police officer carrying a little girl in his arms. The girl wasn't moving.

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