Another report said several were killed while over 100 were injured in the severe storm.
The sheriff said personnel were visiting each house to see whether anybody was trapped, injured or dead inside the debris in the DeCordova Ranch and Rancho Brazos Estates neighbourhoods. About 8,000 people reside in those areas near Lake Granbury.
The Granbury tornado is part of a system of severe thunderstorms that ravaged several tornadoes across North Texas. The tornado learnt to have touched down several times in Hood, Dallas, Tarrant and Parker counties. The National Weather Service said a tornado watch will remain active for more than 30 counties until early morning of Thursday.