Grenade Found on Side on Texas Highway Leaves Authorities Puzzled

Investigators are trying to determine how a poorly-constructed hand grenade ended up on the side of a highway in Brownsville, Texas, authorities told FoxNews.com.

The improvised explosive device was discovered Sunday night on U.S. Highway 77/83. The Brownsville Police Department bomb squad responded and determined that the grenade had no detonation device, Eddie Garcia, the public information officer, said.

As a precautionary measure, police closed the only highway that runs through the town located near the Mexican border.

Police said even if the device detonated, it would have not caused significant damage. There are currently no leads.