Thousands flee torrential rain floods
Flooding caused by torrential rain from the remnants of Tropical Storm Allison has forced thousands of people out of their homes in Houston.
The bad weather also left scores more stranded for hours on flooded freeways, their cars and trucks underwater.
Mayor Lee Brown declared a state of emergency and asked the state for help with boats and rescue crews.
Coast Guard helicopters have been sent to rescue some people from their roofs.
Mr Brown said: "This incident is of such severity, such magnitude, effective response is beyond the city of Houston's capacity to recover without supplementary state and federal assistance."
Some gauges in the city showed nearly 20 inches of rain in 24 hours.
Governor Rick Perry signed a state of emergency declaration for parts of southeastern Texas.
He also asked the federal government to make the specified regions eligible for low-rate disaster relief loans, grants and other assistance.
Brown said at least 3,000 homes and businesses were damaged in Houston and perhaps 10,000 families had been displaced.
All of the city's freeways had been blocked at some point by high water from the new round of rainfall that began early Friday.
The deluge was produced by the lingering remnants of Allison, the Atlantic hurricane season's first named storm, which blew ashore on the Texas coast from the Gulf of Mexico on Tuesday, then quickly dwindled but refused to leave.
In Louisiana, alligators stirred up by the storm's thunder, lightning and heavy rain have been wandering into residential areas.
