Thousands on March for Our Lives gun control rally sign up to vote for first time: 'We will vote them out'

'The more I see people marching and standing up for a cause I believe in, I want my voice to matter, too,' says teenager on march

Activists at gun control marches across America have signed up thousands of first-time voters pledging to eject lawmakers who oppose stricter firearms laws.

Voter registration advocates were out in force as hundreds of thousands of people took part in more than 800 March for Our Lives rallies held across the US on Saturday.

Organisers of the drive were aiming to sign up 25,000 young voters in favour of tougher gun control laws ahead of mid-term Congressional elections in eight months’ time.

Speaking at a rally in Washington, Delaney Tarr, a survivor of the Marjory Stoneman Douglas High School shooting in Parkland, Florida, that left 17 people dead in February, had a simple message for legislators.

"If there is no assault weapons ban passed, then we will vote them out," she said.

Volunteers from electoral registration campaign HeadCount chanted "demonstration without registration leads to frustration" before working through the crowds, signing up new voters en masse at the Washington rally.

One of those who registered, 18-year-old Hugh Williams from Ypsilanti, Michigan, said gun violence had become a “menace” in his community.

"The more I see people marching and standing up for a cause I believe in, I want my voice to matter, too," he said.

Participation in US elections by young voters is often low, and registration activists are targeting the four million Americans turning 18 this year, as well as those aged 19 to 21 who have never voted before.

Any potential increase in young voters is likely to be a boon for Democratic and independent candidates who back stricter controls on assault-style weapons, bump stocks and tighter access to guns for young people and the mentally ill.

In Parkland, Sari Kaufman, another Marjory Stoneman Douglas student, urged her peers to get involved in politics in order to remove lawmakers who did not protect their interests.

"With this movement, we will ensure record-breaking turnout not just in the next presidential election, not in the next midterm election, but in all elections," she told a crowd of thousands.

"We're here today to give you the tools to make a change."

Additional reporting by Reuters