WASHINGTON, U.S. — Following the recent mass shooting in Buffalo, New York, in which 10 people tragically died, senators across the U.S. are rallying behind a letter urging an investigation into the marketing of assault rifles.

Senators Chris Murphy (D-Conn.) and Richard Blumenthal (D-Conn.) joined U.S. Senator Edward Markey (D-Mass.) and eight of their Senate colleagues in a letter to the Federal Trade Commission (FTC) expressing their concerns.

Specifically, the senators are scrutinizing the advertising of assault-style rifles to children.

The letter highlights marketing targeted at children by firearms dealer Wee1 Tactical, which sells the “JR-15,” an assault-style rifle modeled after the infamous AR-15.

Wee1’s marketing to minors includes photos and videos of children on its website and Facebook page wielding the JR-15, as well as Wee1’s logo depicting a pacifier on a skull-and-crossbones.

Lawmakers argue that these marketing tactics are dangerous and irresponsible, especially as the gun violence epidemic continues to skyrocket.

This point was largely underscored by the shooting that took place in Buffalo, at the hands of someone who is only 18-years-old and was wielding an AR-15 rifle.

“We write today to urge the Federal Trade Commission (FTC) to use its authority under Section 5 of the FTC Act to open an investigation into the marketing of highly lethal firearms, including assault-style rifles, to impressionable young people,” wrote the lawmakers in their letter to the FTC. “These are weapons of war that have no place in the hands of our nation’s children, and can cause them substantial harm and even death.”

A copy of the letter can be found here.

Joining Murphy, Blumenthal, and Markey in signing the letter are U.S. Senators Jack Reed (D-R.I.), Dianne Feinstein (D-Calif.), Alex Padilla (D-Calif.), Cory Booker (D-N.J.), Ben Ray Luján (D-N.M.), Elizabeth Warren (D-Mass.), Jeff Merkley (D-Ore.), and Tammy Duckworth (D-Ill.).