US president Barack Obama has made an impassioned plea for tougher gun control laws after another "routine" shooting at an Oregon community college that has left 10 people dead and 7 injured.

Key points: Ten people dead and seven injured

Ten people dead and seven injured Gunman exchanged fire with police, was killed

Gunman exchanged fire with police, was killed Gunman was 20 years old

The gunman opened fire at Umpqua Community College campus in Roseburg, before he was shot dead by police, state and county officials said.

The shooter was identified as 26-year-old Chris Harper Mercer.

He was not publicly identified by local authorities as Douglas County Sheriff John Hanlin vowed never to utter his name.

Mr Hanlin confirmed 10 people had died in the mass shooting, revising down an earlier toll of 13 dead and 20 injured given by the state's attorney-general.

Authorities said the shooting took place in one of the classrooms in the science building.

"It cannot be this easy for somebody who wants to inflict harm on other people to get his or her hands on a gun," Mr Obama told a news conference.

"We've become numb to this.

"Right now, I can imagine the press releases being cranked out — we need more guns, they'll argue. Fewer gun safety laws. Does anybody really believe that?"

Mr Obama said other countries, such as Britain and Australia, had been able to craft laws that prevented mass shootings.

"We don't yet know why this individual did what he did. It's fair to say that anybody who does this has a sickness in their minds," he said.

A patient is taken into the emergency room at Mercy Medical Centre in Roseburg, Oregon, after a college shooting. ( AFP: Aaron Yost/The News-Review )

"Regardless of what they think their motivations may be, we are not the only country on Earth that has people with mental illness or want to do harm to other people.

"We are the only advanced country on Earth that sees these kinds of mass shootings every few months. "

Mr Hanlin said the names of the victims would not be released for 24 to 48 hours pending notification of next of kin.

It was not immediately clear if the gunman was counted in the death toll given by Mr Hanlin.

Mr Hanlin earlier said that officers exchanged fire with the gunman on the Oregon campus, but said no officers were injured.

"Upon arriving there they located the shooter in one of the buildings. Officers engaged that suspect," he said.

"The shooter threat was neutralised."

Mr Hanlin added later: "The shooter is deceased."

CNN reported that four guns belonging to the shooter were recovered from the scene.

Mercy Medical Centre in Roseburg, a city of about 20,000 people 418 kilometres south of Portland, said on Facebook that the hospital had received nine patients from the shooting and had been advised that three more were en route.

The Portland Oregonian newspaper reported that officers responded around 10:40am (local time) to reports of a shooting at the college.

The college was immediately placed on lockdown as firefighters, police and concerned parents rushed to the site.

Authorities set up a triage centre at the college and searched students as they left the facility.

Police officers search students outside Umpqua Community College in Roseburg, Oregon, after a shooting. ( AFP: Michael Sullivan/The News-Review )

'I probably heard 35 to 40 shots'

The unidentified man opened fire in a classroom and moved to other rooms methodically gunning down his victims, witnesses said.

Student Cassandra Welding was in an adjacent room when the shooting broke out.

Authorities check bags as students and staff are moved off campus after reports of a shooting. ( Twitter: Michael Sullivan )

"I probably heard a good 35 to 40 shots," Ms Welding told local media.

She saw a fellow student be shot after opening the classroom door to see what was happening, she said.

"Then we locked the doors, turned off the lights and ... we were all pretty much in panic mode and called 911 (emergency services) and our parents and [said] 'I love yous' because we didn't know what would happen, if those were our last words," Ms Welding said.

Police searched the entire campus after the shooting aided by sniffer dogs and patted down students and staff as they left and boarded buses that transported them to local fairgrounds.

College interim president Rita Cavin said the priority was to reunite students and staff with their loved ones.

"We have families waiting for the last bus of students to arrive and have grief counsellors for those who have no children coming off the bus," she said.

"It's sad to watch the families wait for the last bus."

Gunman may have used social media before shooting: reports

News reports said the shooter may have posted a message online before the shooting.

A chain of messages posted to an anonymous chat board known for its explicit conversation threads and graphic images included an ominous warning on Wednesday night not to go to school on Thursday "if you are in the north-west".

The anonymous postings and numerous replies appeared on the site 4chan.org hours before the shooting.

A helicopter is seen at Mercy Medical Centre in Roseburg after a shooting at a community college in Oregon. ( Twitter: Kelly Andersen )

The thread's authenticity, however, could not be verified, nor could its connection to Thursday's event.

A comparable posting three years ago ahead of the school massacre in Newtown, Connecticut, was later discredited by police.



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School shootings are a disturbing reality of American life and many facilities have reinforced security in recent years, especially in the wake of the Sandy Hook massacre in 2012.

Twenty students and six adults were killed at the Sandy Hook Elementary School in Connecticut by 20-year-old Adam Lanza.

Former politician and shooting victim Gabrielle Giffords tweeted her support for those involved in the attack.

"A community's heart has been tested but will not be broken," she said.

Ms Giffords, a Democrat in Arizona, was shot in the head during a 2011 attack that killed six people.

In the United States the ownership of firearms is protected by the Second Amendment of the US Constitution.

Aerial view of Oregon's Umpqua Community College, where 10 people were shot dead.

ABC/wires