World War I grenade

A screenshot of the grenade, taken from the Los Altos Police Department's Instagram account.

Members of the Santa Clara County Sheriff’s Office Bomb Squad successfully detonated a vintage grenade in a Los Altos backyard Monday afternoon without causing any injuries.

The explosion was initiated as a precaution, according to a Los Altos Police Department press release.

At 10:15 a.m. Monday, the police department received a phone call from a Los Altos resident who discovered a possibly live World War I-era grenade in the bedroom of an elderly relative’s home, located in the 1700 block of Christina Drive, the release stated.

PG&E conducted an underground service assessment prior to the operation, and Santa Clara County Fire Department personnel remained on scene, according to the release. The police department evacuated four adjacent homes and asked the residents of others in the vicinity to shelter in place.

Related: Los Altan traces origins of WWI grenade found in dad’s drawer