Joe Biden calls for tighter gun control measures after Colorado shooting
"This is not and should not be a partisan issue. This is an American issue. It will save lives. American lives. And we have to act."
Tighter gun control is overwhelmingly popular with Americans, but Republicans have long stood against what a minority view as an infringement on their right to bear arms.
Mr Biden spoke hours after a 21-year-old man was charged with shooting 10 people in a supermarket in Boulder, Colorado.
That massacre came less than a week after another gunman shot dead eight people at multiple spas in the Georgia state capital Atlanta.
Source: AAP/EPA/ERIK S. LESSER
Together the killings ignited new calls for politicians to act, but on Tuesday the familiar bipartisan divide was emerging once more.
This month the House of Representatives passed two measures aimed at enhancing background checks and closing a loophole related to a deadly 2015 church shooting in Charleston, South Carolina.
The bills address a hugely popular premise among American voters: that background checks be required for all US firearm sales, including those at gun shows.
But they are unlikely to pass through the Senate, which would require at least nine Republicans to vote for them.
Nevertheless, majority Senate leader Chuck Schumer said he had committed to bringing background checks to the floor.
"This Senate is going to debate and address the epidemic of gun violence in this country," he said on Tuesday.
"We should be able to buy groceries without fear ... But in America, we can't," former President Barack Obama said in a statement.
It is "long past time" for politicians to act, Mr Obama continued.
"We can overcome opposition by cowardly politicians and the pressure of a gun lobby that opposes any limit on the ability of anyone to assemble an arsenal. We can, and we must," he said.
The Senate Judiciary Committee was holding a hearing Tuesday which will be the first of a series to examine proposals to reduce gun violence.
The suspect in the Colorado killings, named Ahmad Al Aliwi Alissa, was in hospital after being shot in an exchange of fire with officers following the Monday afternoon attack on King Soopers in Boulder, 50 kilometres northwest of the state capital Denver.
"He is charged with 10 counts of murder in the first degree and will be shortly transported to Boulder county jail," Police Chief Maris Herold told a press conference.
The police chief also read out, one by one, the names of the 10 people killed in the attack: men and women aged from 20 to 65 including police officer Eric Talley, a 51-year-old father of seven, who was the first on the scene.
"Boulder County is a small community, we're all looking over the list. Do we know anybody?" said Governor Jared Polis at the press conference.
"None of them expected that this would be their last day here on the planet."
Colorado has previously suffered two of the most infamous mass shootings in US history, at Columbine High School in 1999, and at a movie theatre in Aurora in 2012.
Those massacres prompted nationwide soul-searching but did not result in major changes to gun laws.
Source: AP Photo/Damian Dovarganes
The city of Boulder imposed a ban on "assault-style weapons" and large-capacity gun magazines in the wake of the Parkland, Florida shooting in 2018.
But a judge last week blocked that ban, the Denver Post reported, in a decision hailed by the National Rifle Association, a powerful pro-gun advocacy group.
The NRA tweeted a copy of the Second Amendment on the right to bear arms after the Colorado shooting.
Witnesses said they initially heard multiple loud bangs outside the shop.
"I just nearly got killed for getting a soda and a bag of chips," Ryan Borowski, who was in the store when he heard at least eight gunshots, told CNN.
"It doesn't feel like there's anywhere safe anymore."