Democratic presidential front-runner Hillary Clinton heckled at a campaign rally

WASHINGTON: Democratic party presidential front-runner Hillary Clinton has been heckled at a campaign rally by a Republican lawmaker who asked her questions about her husband former US president Bill Clinton's alleged sexual impropriety.

The heckler, later identified as Republican State lawmaker Katherine Prudhomme O'Brien, has for years followed the former first lady, peppering her with questions about allegations of past sexual misconduct by Bill.

Clinton, 68, who is aiming at becoming the first ever woman president of the US and is so far leading the Democratic Party's race, described the repeated disruption in her speech as very rude.

"You are very rude and I'm not never ever going to call on you," Clinton said as O'Brien was repeatedly shouting at the former First Lady and the Secretary of State.

Following the event, O'Brien told reporters that she was trying to ask Clinton about her husband's sexual impropriety decades ago.

"I asked her how in the world she can say that Juanita Broderick and Kathleen Wiley are lying when she has no idea who Juanita Broderick is," she said.

"She told me this summer she doesn't know who she is and doesn't want to know who she is. How can she access that they are lying, which she told someone last month?" O'Brien said.

"I was a Democrat, but I became a Republican because of this, because of this stuff. Because of what I saw happen in the Clinton years, the hypocrisy of so-called women who fight for women," O'Brien said.

Meanwhile, Clinton, who is campaigning in New Hampshire, applauded Obama's soon-to-be-announced executive action that would strengthen background checks and make it harder for dealers to sell guns to criminals.

But Clinton warned how the progress made by this executive order would be reversed if a Republican wins the White House. Republican candidates including Donald Trump, Marco Rubio, Chris Christie and Ted Cruz have already announced their intention to undo this action curbing gun violence.

"When I came out with my proposals for common sense gun safety measures, I did say that in the absence of Congressional action, I would use executive authority to go as far as would be possible under the law and I applaud the President for taking a hard look at that and I believe he will take some actions to require more gun sellers to do background checks," Clinton said of the anticipated proposal.

"I know that a Republican president would delight in the very first day, reversing executive orders that President Obama has made, including this one that we expect him to make," she warned.