Nunez said that authorities recovered a flak jack with steel plates and five magazines lying next to a rifle at the college, adding that more ammunition was found at the shooter’s residence.
Douglas County Sheriff John Hanlin did not announce the names of any of the victims at Friday morning’s news conference but said he expected at least some identities to be released later in the day by the medical examiner’s office.
He declined to name the shooter, saying that doing so “will only glorify his horrific actions” and “service to inspire future shooters.” But a law enforcement source confirmed to Al Jazeera that the suspect was Chris Harper Mercer, 26. He was killed in a shootout with officers following the attack.
That morning, the shooter walked into a writing class at the community college, 180 miles south of Portland, and opened fire, hitting some students with multiple gunshots.
One witness said a teacher was struck in the head. Another said the attacker demanded to know before shooting his victims whether they were Christian. Police officials would not say if they knew of any motive behind the assault.
Mercer isn't believed to have a criminal history. Investigators have suggested that he may have been a student at the college, because a receipt found at the scene showed he purchased textbooks from the campus bookstore two days before the shooting.
Other details of the shooter emerged Friday. Lt. Col. Ben Garrett, an Army spokesman, told Al Jazeera that records indicate that Mercer served in the Army for a month in late 2008 but was “discharged for failing to meet the minimum administrative standards.”
Social media profiles linked to Mercer suggest he was frustrated by traditional organized religion, tracked mass shootings and was fascinated by the Irish Republican Army, Northern Ireland’s now defunct nationalist armed group.
There didn't seem to be many recent connections on the social media sites linked to Mercer, with his MySpace page showing just two friends. He appeared to have at least one online dating profile.
On a torrents streaming site and blog that appeared to belong to Mercer, posts referred to multiple shootings, and downloads included several horror films and a documentary on the mass shooting at Sandy Hook Elementary School in Newtown, Connecticut.
A blog post urged readers to watch the online footage of Vester Flanagan shooting two former colleagues on live TV in Virginia, and another lamented materialism as preventing spiritual development.
The MySpace page that appears to belong to Mercer features several photos and graphics of the IRA as well as a picture of him holding a rifle.
Oregon Gov. Kate Brown, Sen. Jeff Merkley, Sen. Ron Wyden and Rep. Peter DeFazio offered their condolences in a Roseburg press conference on Friday.
"This horrific, senseless act has broken hearts, every heart here," said Merkley.
Wyden urged his fellow lawmakers to seek "common ground" on reforms that would prevent similar shootings from occurring in the future.
"Right now is a time of healing and helping the community," said Wyden. "For the future, it is clear that it does have to be about more than words and good intentions if this carnage is to finally end. As a country, we cannot just shrug our shoulders and move on."
Roseburg city manager Lance Colley said at a press conference that the Red Cross has been running blood drives for victims of the shooting and that there has been an outpouring of blood donations so far.
"There have been blood drives. The one today has been basically overwhelmed," said Colley.
Al Jazeera and wire services