(Reuters) - A handgun was found in the backpack of a 7-year-old boy at a New York City public elementary school on Thursday, triggering a brief lockdown amid heightened concern about gun violence in U.S. schools, officials said.
New York City Police Department spokesman John Grimpel said authorities are investigating how the unloaded .22-caliber handgun ended up in the child's backpack.
Police also found an ammunition clip and a flare gun in the bag belonging to the second-grade student, Grimpel said.
Officials locked down the Wave Preparatory Elementary School, located in Queens, for an hour, the New York City Education Department said.
In December a gunman killed 20 first-graders along with six adults at Sandy Hook Elementary School in Newtown, Connecticut.
On Wednesday President Barack Obama launched the biggest U.S. gun-control push in generations, urging Congress to approve an assault weapons ban and background checks for all gun buyers to prevent mass shootings like the Newtown massacre.
(Reporting by Kevin Gray; Editing by Xavier Briand)