Pro-gun activists held "high noon" rallies across the United States on Saturday to defend the right to own firearms that they say is being threatened by President Barack Obama's gun-control proposals.

The US debate over gun control erupted in mid-December after a man armed with an assault rifle killed 20 first-graders and six adults at an elementary school in Newtown, Connecticut - the deadliest of a string of US shooting sprees last year.

"We are law-abiding citizens, business owners, military, and we are not going to be responsible for other people's criminal actions," former Marine Damon Locke said to applause at a Florida rally he had helped organise.

Some in the crowd of about 1,000 in Brooksville, about an hour north of Tampa, hoisted signs that said: "Stop the Gun Grabbers" and "Gun control isn't about guns, it's about control."

Obama and gun-control advocates have begun a push to reinstitute a US assault weapons ban following the Connecticut massacre. A number of other states have taken up gun legislation, and New York, with among the strictest gun control laws in the country, broadened its assault weapons ban on Tuesday.

Obama has also called for a ban on high-capacity magazines and more stringent background checks for gun purchasers.

On the day the pro-gun rights rallies were being held across the country, five people were wounded in accidents at three gun shows.

Three people were hurt when a 12-gauge shotgun discharged as its owner opened its case at the entrance to a show in North Carolina. Two others were wounded when guns went off accidentally at gun shows in Ohio and Indiana. None of the day's injuries was life-threatening.

DEFIANT MOOD

In Connecticut, a rally for gun rights drew about 1,000 people at the state Capitol, where lawmakers have reacted to the Newtown shooting with proposals to tighten gun-control rules, including limiting access to assault weapons and high-capacity magazines.

That did not sit well with gun owner Jessie Buchanan, who attended the rally in Hartford.

"They could take away the 10-round magazine today and tomorrow it would be the five-round and the next day it would be the whole thing," Buchanan said.

In Denver, the mood was defiant as about 500 people, including families with children, gathered in unseasonably warm weather outside the state Capitol.

"I have earned the right to have my guns," said Don Dobyns, an Air Force veteran and former police officer from Colorado Springs, who was among the rally organisers.

Sporting a shirt that read, "Girls with guns," 31-year-old Jennifer Burk said, "My parents didn't raise a victim and the government shouldn't try and make me one."

Gun-control advocates say US civilians have no justifiable need for assault weapons or high-capacity magazines, and they say more background checks will help keep guns out of the hands of criminals.

The reaction has been fierce from gun supporters such as the National Rifle Association, who point to a right to bear arms that is enshrined in the Second Amendment to the US Constitution and which they do not want to see watered down.

On Sunday, gun-control advocates plan to hold a National Gun Prevention Sabbath, where they say 150 houses of worship will call on the faithful to advocate for an "actionable plan to prevent gun violence."

People who have lost loved ones to gun violence will display their photographs, organisers said. – Reuters