Explosives were found under a Central Texas highway bridge and investigators are trying to determine who left the items and why.

A bomb squad was summoned Tuesday night after the suspicious objects were discovered under an FM 1963 bridge near Rosebud.

McLennan County Sheriff Parnell McNamara said officers determined a flammable liquid, a detonator, some shotgun shells and shrapnel were inside a container. A water cannon was used to break apart the container, for further testing on the items inside.

Nobody was hurt. Authorities didn't immediately say who found the explosives.

Rosebud is 90 miles northeast of Austin.