The Chicago police bomb squad was on the scene of live grenade Tuesday morning in Austin on the West Side.
Police responded to a call of a suspicious package about 9:35 a.m. in the 5000 block of West Madison Street, according to preliminary information from Chicago police.
The bomb squad later determined there was a live grenade inside a blue lunch bag, police spokeswoman Sally Bown said.
Surrounding streets were closed as police secured the grenade.
Last week, a World War II-era grenade was discovered in a park in north suburban Highland Park.