After Thursday's mass shooting at an Oregon community college, which left nine people dead and more injured, President Obama aired his frustration over gun laws in the U.S. At a news conference Friday, he called on voters to push their representatives to take action.

"You just have to, for a while, be a single-issue voter, because that's what is happening on the other side," Obama said. "And that's going to take some time. I mean, the NRA has had a good start."

Authorities are trying to build a profile of the 26-year-old gunman who shot and killed 9 people and wounded as many at a western Oregon community college on Thursday in hopes of discovering what his motive might have been.

The Douglas County Sheriff, John Hanlin, has refused to say the shooter's name, stating that he doesn't want to "glorify" him, but officials have said he is Christopher Sean Harper-Mercer and that he was killed at the scene in a shoot-out with police.

Here's what we know about him:

You might have seen the article by now: " 'No Way To Prevent This,' Says Only Nation Where This Regularly Happens." The Onion, a satirical news site that runs fake news stories, has published a story with that headline three times over the last year and a half: this week after a shooter killed nine people at an Oregon community college; in June of this year after a violent rampage in a black Charleston church that also killed nine people; and last May, after a shooting at the University of California Santa Barbara that killed seven.

Douglas County Sheriff Vows To Not Use Shooter's Name

Oct 2, 2015

At a press conference Friday morning Douglas County Sheriff John Hanlin repeated his vow about the Roseburg, Oregon, shooter who killed 10 people on Thursday.

Authorities in Oregon released the names of the nine people killed during a mass shooting at a community college in Roseburg, Ore.

John Hanlin, the Douglas County sheriff, read the names during a news conference Friday afternoon:

The victims ranged in age from 18 to 67. One of them was an 18-year-old soccer player, another had just enrolled at the college at 34 years old. Another 18-year-old was just about to take his brown belt test.

How Trauma Ripples Through A Community

Oct 2, 2015
Community members gather for a candlelight vigil for those killed in a shooting at Umpqua Community College in Roseburg, Ore., Thursday, Oct. 1, 2015.
AP Photo/Rich Pedroncelli

Jeannie Yandel sits down with Dr. Doug Zatzick, a professor of psychiatry at the University of Washington who also works with PTSD patients at Harborview Medical Center, to discuss how the Roseburg community can recover from the tragic mass shooting at Umpqua Community College in Oregon.

Chris Mintz was shot multiple times by a gunman at an Oregon community college Thursday, and now he's being called a hero, after it emerged that Mintz ran at the attacker and tried to block the door to a classroom and protect his classmates. Mintz is now recovering from surgery.

“A profound sense of loss.”

Those are the words Washington Governor Jay Inslee used to describe the shooting at Umpqua Community College in Roseburg, Oregon.

Harborview Hospital, Seattle, 2002
Flickr Photo/Seattle Municipal Archives (CC BY 2.0)/

A new federal grant gives Harborview Medical Center a boost in combating gun violence. The U.S. Department of Justice on Friday awarded about $500,000 to organizations in Seattle, including Harborview.

The hospital wants to talk with gunshot victims about the reasons they ended up in the hospital -- sometimes due to gang activity or crime. 

Jaylen Fryberg, the 15-year-old who shot five friends in the cafeteria at Marysville-Pilchuck High School in October.. Jaylen and four of the friends died.

Minutes before a Washington state high school freshman fatally shot four friends and then himself, he sent a group text message to his family outlining his funeral wishes and apologizing to the parents of the teenagers he was about to kill.

 Grist's Katie Herzog, Crosscut's Knute Berger, KUOW's Bill Radke and Seattle Channel's Joni Balter in the KUOW offices on Friday, Aug. 28, 2015.
KUOW Photo/Gil Aegerter

Bellevue High School’s dominant football program is investigated over an alleged “diploma mill.” Gun rights groups sue Seattle over its “gun violence tax.” Has Amazon energized Seattle or ruined it?

Bill Radke reviews the week’s news with Crosscut’s Knute Berger, Seattle Channel’s Joni Balter and Grist’s Katie Herzog.

A jury in Colorado has found Aurora theater shooter James Holmes guilty of first-degree murder in the 2012 mass shooting that killed 12 people and injured 70 others. Holmes could now face the death penalty.

The jury of nine women and three men, who heard nearly three months of testimony in the case, deliberated for a day and a half before arriving at a decision on Thursday.

The verdict comes nearly three years to the day after the mass shooting on July 20, 2012, at the Century Aurora 16 theater.

More than 30 cities and counties in Idaho have changed local laws on firearms or eliminated signage prohibiting guns in public places over the last year. It’s all the result of a systematic effort by one gun-rights group.

home, house, housing: An aerial shot of the Greenwood neighborhood in Seattle, 1969.
Flickr Photo/Seattle Municipal Archives (CC-BY-NC-ND)

A draft city report pokes at Seattle’s single-family character. Also: Why don’t we rope off the dangerous Big Four Ice Caves in the Cascades? Would a Seattle gun tax infringe on your right to bear arms? And in a super-dry Seattle summer, should you be conserving water, or not?

Bill Radke debates the week’s news with Crosscut's Knute Berger, journalist Tonya Mosley and former state GOP chair Chris Vance.

Each year, convicted felons get thousands of weapons from licensed gun dealers. They skirt the mandatory background checks by having people who do qualify fill out the paperwork for them.

Now, the settlement of a lawsuit over a tragic murder-suicide in Kansas has made it easier to sue gun dealers who allow these "straw purchases" with a wink and a nod.