NEW YORK
At least 18 people have been found dead in Texas and Oklahoma from a storm system that ravaged the U.S.'s fourth largest city, local media said Wednesday.
Houston was gripped by another round of local heavy rain Wednesday morning, after nearly 28 centimeters (11 inches) of torrential rain led to massive flooding of streets, freeways and bayous just in the past day.
The city said at least five people were killed, two remain missing and more than 1,400 buildings damaged.
"The defining feature of Houston is the small rivers that run through the city," Mayor Annise Parker said during a press conference.
"Many of them went over their banks and began to flood neighborhoods," she added.
More rain was expected Wednesday evening in the area including Houston and Dallas-Fort Worth, said the National Weather Service.
"Damaging winds and large hail will be the main threats, with an isolated risk of tornadoes across parts of the central and southern Plains," it said.
With floodwaters beginning to recede in parts of Texas and Oklahoma, more bodies surfaced, bringing the overall death toll to 18, CNN said.
In addition to the five dead in Houston, three deaths have been reported in Hays County, as well as one death each from Medina, Milam, Travis and Williamson counties.
Six people reportedly died from the storm in Oklahoma this past weekend.
President Barack Obama on Tuesday pledged federal assistance to the region.
Texas Gov. Greg Abbott has declared 46 counties in central Texas disaster areas since heavy rains began falling.
Severe thunderstorms are expected Thursday from Nebraska to West Texas in the afternoon and evening, the Weather Channel said.
"Overnight clusters of storms are possible in western/southern Oklahoma and western/central Texas," it added.
At least 13 others were killed in northern Mexico because of the same storm system, according to reports.
