UPDATE:

The gunman who opened fire at a community college in Roseburg, Oregon, on Thursday, asked people in an academic building to stand up and state their religion before he began shooting, a witness told the local News-Review newspaper.

Kortney Moore, 18, was in Snyder Hall when the shooter asked people to name their religion and then began firing, she told the paper.

The gunman has been identified as Chris Harper Mercer, 26. "He appears to be an angry young man who was very filled with hate," a law enforcement official told the New York Times.

He was reportedly armed with four guns, three handguns and an AR-15-style long gun, according to CNN. He had a shootout with police and it is not known yet whether he was killed by police or killed himself.

This is a breaking news story. Check back for updates.

EARLIER STORY: Oct 1 (Reuters) - A gunman opened fire on Thursday at a community college in Oregon, killing 13 people and wounding some 20 others before he was shot to death by officers, in the latest mass killing to rock a U.S. school, state and county officials said.

There were conflicting reports on the number of dead and wounded in the shooting rampage at Umpqua Community College, which began shortly after 10:30 a.m. local time (1730 GMT).

The state's attorney general told the local NBC affiliate that 13 people had been slain, 20 wounded and the shooter was killed.

The shooting is the latest incident of gun violence in the United States, raising demands for more gun control and more effective treatment of the mentally ill.

Douglas County Sheriff John Hanlin said the gunman was slain in an exchange of gunfire with police officers in a campus building.

"It's been a terrible day," Hanlin said. The sheriff did not say how many people had been slain or wounded at the college in Roseburg, a city of about 20,000 people some 260 miles (418 km) south of Portland.

"This is a peaceful community," he said. "We have our share of crime like any community but certainly this is a shock to have this level of a crime."

Governor Kate Brown said the suspect was 20-year-old man but he was not identified further by authorities.

In an emergency call from the incident posted onto the website of the Oregonian newspaper, an emergency responder at the scene said there were unconfirmed reports the shooter had a long gun. A short time later, an emergency responder radioed that the suspect was "down."

CNN reported that among the wounded was a female who had been shot in the chest. The Oregonian said that at least six patients were critically injured in the shooting, citing an official with Life Flight.

Andi Dinnetz, an 18-year-old freshman at Umpqua, said she was in the building next to where the shooting took place and hid in a welding shop along with a teacher and classmates until a police officer arrived. She said she was "fine, but shaken."

"They walked us straight through the crime scene with our hands up," Dinnetz said. "It was more tense outside. In the classroom, everyone was trying to make jokes and keep it from being as serious as it was."

Roger Sanchez, a testing coordinator at the school, said students came running into the building where he worked.

"They came in running and we went into lockdown," Sanchez said. "I knew it was serious."

Mercy Medical Center in Roseburg said on Facebook that the hospital had received nine patients from the shooting and had been advised that three more were en route.

"Please continue to pray," the hospital said.

Local media reported that authorities were combing through the campus, which serves more than 13,000 students, 3,000 of them full-time. The FBI said it was sending agents to the scene. Fall term began at the college on Monday.

The Douglas County Sheriff's Office said students and faculty members were being bused to the nearby fairgrounds where they could be picked up.

President Barack Obama was briefed on the shooting by Lisa Monaco, his homeland security adviser, a White House official said.

The FBI said agents were responding from offices in Medford, Eugene, Salem and Portland.

The Oregonian said agents from the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives were also en route to Roseburg.

Recent episodes of gun violence in the United States include the massacre of nine people at a South Carolina church in June and the killing of five U.S. servicemen in Chattanooga, Tennessee.

In 2012, seven students at the small Christian college Oikos University in Oakland, California, were shot dead by a former student, marking the deadliest outburst of violence at U.S. college since April 2007, when a student at Virginia Tech University killed 32 people and wounded 25 others before taking his own life.

(Reporting by Shelby Sebens and Courtney Sherwood in Portland, Eric M. Johnson in Seattle, Sharon Bernstein in Sacramento, Suzannah Gonzales in Chicago, Katie Reilly in New York and Alex Dobuzinskis and Dan Whitcomb in Los Angeles; Writing by Dan Whitcomb; Editing by Sandra Maler and Lisa Shumaker)