Orange County sheriffs safely detonated a possibly inert hand grenade found in Costa Mesa's Fairview Park, authorities said Wednesday.
About 5:50 p.m. Tuesday, an elderly man notified officials at the Placentia Avenue fire station near Estancia High School that he had spotted a grenade near the walking trails in the park's northern section, according to Costa Mesa police.
Firefighters and Sheriff's Department bomb squad personnel later found the grenade, believed to be from World War II or the Vietnam War, near the park's Wetlands & Riparian Habitat.
It was detonated in the park away from residents, according to police.
The device might have been dug up by an animal near its burrow, police said.