WASHINGTON, Oct. 1 -- U.S. President Barack Obama on Thursday slammed Congress and gun-rights lobby groups for obstructing reforms of gun control laws after an Oregon college campus shooting left 10 people dead.

Lamenting that mass shootings had become "routine" in the United States, Obama said just as his televised condolence had become routine, so had reaction from politicians and opponents of stricter gun laws.

"Someone will comment and say, 'Obama politicized this issue,'" said Obama in his 15th statement on mass shootings since taking office. "This is something we should politicize. It is relevant to our common life together, to the body politic."

Also in his speech on Thursday, Obama called on U.S. gun owners "who are using those guns properly, safely" to start questioning whether the gun-rights lobby group represents their views.

Obama did not mention the National Rifle Association by name, but his remarks hit flat on the powerful organization which holds sway in Washington politics.

"We collectively are answerable to those families who lose their loved ones because of our inaction," Obama added.

Following the 2012 school shootings in Newtown, Connecticut, which claimed 28 lives, including 20 children, the Obama administration initiated but failed to push stronger gun control laws.

The laws, whose sections included expanded background checks and bans on assault weapons, were stymied in Congress after staunch opposition from Republican lawmakers and gun-rights lobby groups.

During his presidency, Obama has been confronted with more than a dozen of high-profile mass shootings, and in an interview earlier this year he called the failure to reform U.S. gun laws "one of the greatest frustrations" of his presidency.

"If you ask me where has been the one area where I feel that I've been most frustrated and most stymied, it is the fact that the United States of America is the one advanced nation on Earth in which we do not have sufficient common-sense gun safety laws, even in the face of repeated mass killings," Obama told BBC in July.

Ten people were killed and at least 10 more injured Thursday in a campus shooting at Umpqua Community College in Roseburg, southern Oregon, state police confirmed.

The gunman was said to be a 20-year-old male who started the carnage before having an exchange of fire with police.

Sheriff John Hanlin of Douglas County told a news briefing about three hours later that the lone shooter was dead on the scene.