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A rain-packed tropical depression has slammed into the Texas-Mexico border region. It poses a new threat to cities already struggling with floods along the Rio Grande and its tributaries.
Tens of thousands of people have been forced from their homes in Mexican towns. Officials have been diverting water from near-capacity dams into other river systems so they don't overflow.
Mexican President Felipe Calderon listened to the latest damage reports at an emergency meeting in the border city of Matamoros on Thursday.
The tropical depression is expected to dump 10 to 20 centimeters of rain across the area.