Spanish authorities say there are multiple victims after flash floods swept away cars, turned village streets into rivers and disrupted rail lines and highways.
The regional president of eastern Valencia, Carlos Mazon, said it was still too early to give an exact figure of the dead, with many people still missing.
Mr Mazon spoke after Spanish national broadcaster RTVE said 13 bodies were recovered in Valencia, citing the Civil Guard.
The Civil Guard did not immediately answer calls from The Associated Press.
Rainstorms on Tuesday caused flooding in a wide swath of southern and eastern Spain.
A high-speed train with nearly 300 people on board derailed near Malaga, although rail authorities said no-one was hurt.
High-speed train service between Valencia city and Madrid was interrupted, as were several commuter lines.
Storms were forecast to continue through Thursday, according to Spain’s national weather service.
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