PUPILS across the US marked the 19th anniversary of the Columbine school massacre yesterday by staging mass walkouts in protest at gun violence.

The national walkout was organised following the Parkland school shooting in Florida in February, in which 17 people were killed.

Demonstrations were held in every state in the US with students making calls to their senator’s offices demanding reforms to gun laws.

They held 13 seconds silence in memory of those killed at Columbine.

More than 2,000 schools took part in the action, which has drawn widespread support from teachers, politicians and celebrities.

Actors Robert de Niro and Julianne Moore both penned letters for pupils to deliver to their teachers excusing their absence from school.

Mr de Niro wrote demanding a “safe, nurturing environment” for children’s education and growth. He said that gun violence is a “devastating disease” with 46 children and teens shot every day, four of them murdered.

“What an opportunity to teach these kids history by encouraging them to make history. Let them learn about the American tradition of protest for change as they experience it,” he added.

The 1999 Columbine shootings sparked a major debate over US gun laws. 

However there have been a further 25 fatal school shootings since then, including those at Sandy Hook and Virginia Tech.

Mass demonstrations followed the Parkland school shooting with pupils demanding politicians and companies cut their ties with the influential National Rifle Association (NRA) which has lobbied against gun reforms, threatening to sue those proposing restrictions.

American Federation of Teachers President Randi Weingarten announced that the union had cut ties with Wells Fargo, after its chief executive Tim Sloan failed to follow up on meeting with the union to discuss the bank’s relationship with the NRA and gun manufacturers.