Grenade thrown into Tijuana police substation

SAN DIEGO (Border Report) — Around 6 a.m. Thursday, a group of men threw a grenade into a Tijuana Police substation on the east side of the city.

The explosive landed in a patio inside the building.

It did not detonate, but officers reportedly ran for cover when they realized what it was.

When the object did not explode, the facility was evacuated and a National Guard explosives unit was called in.

The immediate area was also cleared out and all the patrol cars and employee vehicles were moved away station.

An elementary school next door was locked down during the operation to clear the device.

The National Guard determined it was a real grenade and removed it from the premises without incident.