Hillary Clinton was told 'you owe black people an apology' when she was confronted about controversial comments she made on mass incarceration.

During a fundraising event in Charleston, South Carolina, Black Lives Matter activist Ashley Williams held a sign quoting comments the presidential hopeful made in 1996, when she said "we have to bring them to heel".

When Ms Clinton reads the sign, Ms Williams tells her: "We want you to apologise for mass incarceration.

"I'm not a 'super-predator', Hillary Clinton. Can you apologise to black people for mass incarceration?"

Bill and Hillary Clinton greet supporters during a caucus day event at in Las Vegas (Getty)

"Can I talk?" the former Secretary of State replies, before continuing her speech.

However, Ms Williams continues, saying: "You owe black people an apology."

"You know what? Nobody's ever asked me before," Ms Clinton replies, as a man takes the activist by the waist and leads her away.

"You're the first person to ask me, and I am happy to address it. But you are the first person to ask me."

Speaking in support of the 1994 crime bill, Hillary Clinton said: "They are not just gangs of kids anymore.

"They are often the kinds of kids that are called 'super-predators'. No conscience, no empathy.

"We can talk about why they ended up that way, but first we have to bring them to heel."