Witnesses Describe Chaotic Scene of Umpqua Community College Shooting

— -- Witnesses described a frightening and chaotic scene Thursday after a gunman opened fire at Umpqua Community College in Oregon, leaving at least 10 dead.

Kenneth Ungerman said that he was outside Snyder Hall in Roseburg, Oregon, and was talking to a National Guard recruiter when he heard a gunshot.

"I saw a male with a gun go around the corner to Snyder Hall," he told ABC News. After that, he heard some more shots and ducked behind his Jeep.

"Heard two more gun shots," he said. "People were screaming...We got out, heard more gunshots.

After that, the men told people in the parking lot to get out.

"We got down to the road and stopped traffic," said Ungerman, who said he had military training. "We didn't want anyone else to go up to campus."

The motive for the shooting, which erupted before 10:40 a.m., was unclear, but investigators were poring over messages the gunman -- identified as Chris Harper Mercer, 26, by three law enforcement sources briefed on the case -- left behind. Three pistols and an AR-style rifle were found at the scene, sources said.

It was not clear if the shooter, who was killed in a gun battle with police, was counted among the 10 dead.

Another student, Hannah Miles, said that she heard shot from another classroom and then huddled together with others students, the Associated Press said.

A man told them to "come on out, come on out," but they didn't open the door, the AP said.

Kortney Moore said that she was in a writing class when a bullet tore through the window, according to the AP, citing the Roseburg News-Review.

She said that the gunman came into the classroom, told people to get on the ground and then asked people about their religion.