Explosion Threat Prompts 91 Freeway Closure After Big Rig Catches Fire

RIVERSIDE, CA -- Eastbound and westbound lanes of the 91 Freeway were shut down Thursday morning after a big rig caught fire near Adams Street, according to the California Highway Patrol.

The fire was reported around 11:30 a.m., according to CHP.

Riverside Fire Department said the blaze posed a threat for possible explosion.

CHP said a SigAlert has been issued and the freeway closures are a mile long in both directions. The closures could last for two hours.

No additional information was immediately available.

Follow this developing story for updates.