A Gilbert charter school was forced into lockdown Thursday after police found a grenade casing near the campus.
The grenade did not have the explosive material to make it a threat, according to Gilbert police Lt. Eric Shuhandler.
The Gilbert bomb squad reported to the scene, near the intersection of Baseline Road and Stonehenge Drive, at 7:45 a.m.
Edu-Prize Charter school was allowed to reopen at 8:15 a.m., Shuhandler said.
A parent informed workers at the front desk of the school about the explosive device, according to principal Robbie McCamman.
"We actually practiced a lockdown drill yesterday," he said.
In Thursday's lockdown, students were held inside until police informed the office that it was safe to come outside, he said.