Corona police responded to reports of a suspicious U-Haul truck that had been sitting in a parking lot for about two days. The windows were covered and an unknown type of fluid was coming out of the cab.
A hazardous-materials team and a bomb squad were called to the scene. A remote-controlled robot smashed the front passenger-side window. That's when firefighters found the woman inside.
She was unresponsive but was reported in stable condition in an area hospital. Family members said she has a history of schizophrenia.
No hazardous materials were found in the truck.
The investigation shut down the 91 and 71 freeways in Corona for about two hours Friday afternoon, snarling traffic for miles.