Slideshow ( 2 images )

NEW YORK (Reuters) - Gun-control advocacy group Everytown for Gun Safety said on Friday it will donate up to $2.5 million to support marches around the United States on March 24, the date of a planned March For Our Lives in Washington to demand an end to school shootings.

They are calling for the Republican-controlled U.S. Congress to overhaul gun laws to make schools safer in a country where school shootings happen multiple times a year.

The deadly shooting last month at Marjory Stoneman Douglas High School in Parkland, Florida, in which 17 people were killed, gave rise to a student-led movement organizing the planned march in the nation’s capital.

Organizers said more than 300 other related events are being organized in support of the march both in the United States and abroad. Everytown will give grants of $5,000 to organizers of up to 500 “sibling” marches, to help with permits, equipment rentals, transportation and other costs.

“Students are making history and demanding that our elected officials protect them,” John Feinblatt, Everytown’s president, said in a statement. Everytown is a non-profit group founded by Michael Bloomberg, the billionaire founder of the Bloomberg media company and former New York City mayor.

Bloomberg, a longtime advocate of gun control, established Everytown in the wake of the 2012 Sandy Hook Elementary School massacre in Newtown, Connecticut. The group works to elect lawmakers willing to make background checks for gun sales more stringent, among other tougher gun-control measures.

Many student survivors of the Florida shooting have emerged as prominent advocates for greater gun control. They hope to tip the balance in a long-running national debate over how much regulation is permitted by the U.S. Constitution’s Second Amendment, which the U.S. Supreme Court has ruled guarantees an individual right to have guns.

U.S. President Donald Trump, a Republican, has suggested steps including training teachers to carry concealed guns and confiscating guns from people deemed to be dangerous without due process rights.

Republican lawmakers in Congress have said they want to improve the national background check system.