Giffords implores Congress for gun control
Wounded former Representative Gabrielle Giffords has implored Congress to curb gun violence, at the first hearing on the issue this year on Capitol Hill.
The Arizona Democrat, who was shot in the head in a 2011 attack that killed six people, said too many children were dying in shootings.
But the National Rifle Association told the Senate judiciary committee that gun control was not the answer.
The renewed gun-control drive follows last month's massacre in Connecticut.
Twenty children and six adults were killed in the attack at a primary school in Newtown, which shocked a nation with the world's highest rate of gun ownership. Firearms sales in the US have risen since the shooting.
Ms Giffords, who is still recovering after being shot by a mentally ill gunman while meeting her constituents in Tucson, opened Wednesday's hearing saying: "Violence is a big problem.
"Too many children are dying. Too many children. We must do something. It will be hard. But the time is now. You must act. Be bold. Be courageous. Americans are counting on you."
Her husband, former astronaut Mark Kelly, also testified.
The couple, both gun owners, recently launched a political action committee, Americans for Responsible Solutions, intended to combat firearms violence.
During the hearing, reports of another mass shooting emerged from Ms Giffords' home state.
Police in Phoenix, Arizona, said three people had been shot - one killed and two others critically wounded - at an office complex. The gunman's whereabouts were unknown.
NRA opposes checks
Wayne LaPierre, executive vice-president of the NRA, an influential firearms lobby group, told Wednesday's hearing that gun control measures had failed in the past.
President Barack Obama this month proposed sweeping measures on guns, including a renewed ban on assault rifles and wider background checks on buyers.
But Mr LaPierre said the government's own figures had shown the last assault-weapons ban from 1994-2004 made no impact on lowering crime.
"Law-abiding gun owners will not accept blame for the acts of violent or deranged criminals," said Mr LaPierre.
"Nor do we believe that government should dictate what we can lawfully own and use to protect our families."
Under questioning, Mr LaPierre conceded that his organisation no longer supported universal background checks for gun owners.
The Senate judiciary committee is divided on the White House plans, which face a rocky road in both the Democratic-led Senate and Republican-controlled House of Representatives.
Republican Senator Orrin Hatch said on Tuesday that he was "a strong supporter of the second amendment" - referring to a clause in the US Constitution on the right to bear arms.
"And I don't intend to change," he added.
Another member, Democratic Senator Dianne Feinstein, has already introduced a bill, similar to the White House plan, that would seek to ban assault weapons and limit ammunition magazines to less than 10 rounds.
But Democratic Senator Charles Schumer said he believed it would be possible to introduce wider background checks.
Those buying guns from licensed stores and vendors are required to face a background check, but some purchasers buying guns from private sales at firearms shows and online do not need to do so, an exception often referred to as the gun-show loop-hole.
President Obama has called for background checks in both instances, as well as increased reporting by states on those who are not allowed to buy a gun for legal or mental health reasons.
The hearing also took place on the day it emerged that a 15-year-old girl who performed at President Obama's inauguration last week had been shot dead in Chicago.
Hadiya Pendleton was attacked by a gunman who opened fire on her and friends as they sheltered from rain in a city park. Police suspect the attacker mistook the group for gang members.