Several tornadoes slammed into homes near Granbury, demolishing homes and killing at least six people, according to the Hood County sheriff.
Hood County Sheriff Roger Deeds said that six people had been killed and the death toll "could climb higher."
"It's definitely a nightmare," he said.
At least fourteen people are unaccounted for as of midnight, but authorities are still working on an updated number, he said.
Rescue crews will search the area at daybreak, but deputies are confident that they have found all of the victims, Deeds said. Emergency workers were going home to home in the DeCordova Ranch and Rancho Brazos Estates neighborhoods, which are in the southern part of town.
Deeds said three tornadoes have been reported. The twisters damaged areas three miles east of Granbury that have about 110 homes, he said.
"Most all of that is heavy damage," he said.
More than 90 people have been evacuated, and about 10 are in shelters overnight. Authorities are still working on getting a count of how many people have been evacuated, Deeds said.
Deeds said the storm intensified at about 7:30 p.m., and reports of rotation came in at about 8 p.m.
"It was horrible. ... The house started shaking," one witness said. "We were in a closet. You could hear it -- it sounded like a train going off. It was scary."
The latest news from around North Texas.
He said his house was fine but "everyone else's was horrible."
Another witness described it as being "like hell."
Lake Granbury Medical Center said it received more than 40 people with injuries such as minor abrasions, fractures and other injuries. Deeds said 14 were admitted, while another 16 people were taken to Fort Worth hospitals.
People searching for family members are asked to call 817-579-2888.
NBC 5's Scott Gordon said people with minor injuries could be seen helping people with more serious injuries when he arrived on the scene Wednesday night.
Gordon reported "widespread damage," saying he saw houses blown to pieces. He said he had not seen the worst-hit areas.
Witnesses said homes in the area were leveled.
"There's nothing left," one man said.
A triage center was set up at Davis and Canyon roads, and school buses were called in to help transport people. Deeds said 250 people in total were taken away from the damaged areas.
The American Red Cross has opened two shelters -- First Christian Church of Granbury at 2109 West U.S. Route 377 and Granbury First United Methodist Church at 301 Loop 567.
People with questions about the tornado in Hood County can call 682-498-8010.
Schools will be open on Thursday, Deeds said.
The tornado was part of a system of severe thunderstorms that spawned several tornadoes across North Texas and dropped large hail in some areas. According to preliminary reports, there were 10 tornadoes in North Texas on Wednesday night.
Large wedge tornado reported near Cleburne
Injuries are reported in Cleburne, where a mile-wide tornado was reported Wednesday night, NBC 5's Omar Villafranca reported.
Downed trees and power outages were also reported in Cleburne, which was declared a disaster area early Thursday morning.
Heavy damage was reported at Gerard Elementary School, but the extent of the damage was not immediately known. State troopers cordoned off part of the area near the school.
Homes near the school were damaged, Villafranca reported.
A Johnson County constable confirmed that there were injuries. Ambulances were spotted leaving the area.
Storm spotters reported seeing a mile-wide tornado five miles northwest of Rio Vista at 9:19 p.m.
Heavy damage was reported in Cleburne a short time later, but it was unclear what had caused the damage. In addition to the tornado, Cleburne also also saw heavy winds of 75 mph to 85 mph winds.
Keaton Taylor, the assistant manager of a Home Depot in Cleburne, said there is a lot of damage in the area. The store is staying open all night for people who need supplies or shelter.
There were also reports of another tornado in Hood County at about the same time.
Another tornado hit the small town of Millsap, about 40 miles west of Fort Worth. Parker County Judge Mark Kelley said roof damage was reported to several houses and a barn was destroyed, but no injuries were reported.
Hail up to the size of grapefruit pelted the area around Mineral Wells on Wednesday evening, but police dispatcher reported only minor damage.
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NBC 5's Scott Gordon, Omar Villafranca and Chris Van Horne contributed to this report.