A Fairfax County bomb squad disposed of an inert grenade found in the parking lot of a Vienna automotive store Wednesday morning, police said.

An employee of the Merchant’s Tire and Auto Center on Maple Ave. discovered the device around 7:30 a.m. and alerted authorities, Vienna Police said.

Authorities shut down Maple Avenue between Lawyers Road and Center Street as they investigated, police said.

The Fairfax County bomb squad then used a robot to remove the grenade, police said. Investigators determined the grenade had no explosive material inside and Maple Ave. was reopened shortly after 9 a.m., police said.

Police said it was unclear who left the device in the parking lot or why it was left there.