KDFW-TV reported a line of storms moving through North Texas had spawned multiple tornadoes that caused damage to homes, large hail and heavy rains.
The Dallas Morning News reported Granbury officials requested medical help from other counties.
WFAA-TV said the American Red Cross said based on initial reports it believed Hood, Johnson, Parker, Wise and Montague counties had received the most damage.
The newspaper said power outages had darkened thousands of homes in the Grand Prairie area and elsewhere in the region.
A tornado was on the ground near Granbury and the nearby Rancho Brazos subdivision was evacuated after about 40 homes were damaged. There were reports of people injured and a possible gas leak.
The tornado in Millsap captured by Storm Chase Media.
There are multiple fatalities, reports CNN.
Kathy Jividen, a spokeswoman for the Hood County, Texas, sheriff's office said there were "multiple fatalities" in the wake of the storm.
Hood County Judge Darrell Cockerham said there were reports of homes being flattened with people inside.
Granbury was pummeled by baseball-sized hail and Millsap was hit by hail stones bigger than golf balls, reports UPI.
Video posted to YouTube appears to show the tornado in Granbury, Texas.
UPDATE — May 16, 2013, 12:14 a.m. EDT: Image showing some of the destruction in Granbury.
UPDATE — May 16, 2013, 1:17 a.m. EDT: Sheriff says six people were dead on the scene and the number could climb higher.
Update - 7:30 a.m. EDT: Sheriff says up to 100 people are injured and 14 are unaccounted for in tornado aftermath.
Update - 9 a.m. EDT: The estimate of those injured has significantly decreased. Seven of the 14 people unaccounted for have also been found.
Michelle Broder Van Dyke is a reporter and night editor for BuzzFeed News and is based in Hawaii.
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