A 911 dispatcher told KGTV-TV, San Diego, a fleet of ambulances had been dispatched to the crash site to handle as many as 30 injured people.
The crash occurred on southbound Interstate 15 near Fallbrook Thursday afternoon as a series of rain storms moved through the area. The bus wound up on its side, blocking several lanes of the busy freeway.
It was not immediately known what company was operating the bus or where it was traveling to.
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