Police say four were killed in accidents that occurred during the massive storm
At least seven people have died in the Dallas area after at least four tornadoes were spawned by severe storms.
Four of the victims were killed in vehicle accidents near the intersection of two major highways in Garland, east of Dallas, police said.
Garland police spokesman Joe Harn said the four were killed in accidents that occurred during the massive storm, but it is unclear if all of them were in the same vehicle.
Police confirmed three more deaths, but gave no further details.
The National Weather Service reported that at least four tornadoes touched down near Dallas.
They reportedly caused heavy damage as they moved northwards, with power cut to thousands, cars upturned, trees flattened and roofs blown from buildings.
The full extent of damage will not be known until daylight on Sunday.
Mr Harn said there were no active rescues under way, although emergency services were continuing to search houses for anyone trapped since the storms passed.
Police say several people have also been injured in the town of Rowlett near Garland, although the exact number is not yet known.
"As of right now, we are still in the search and rescue mode. We still have some homes that have been demolished and not everyone in the homes has been accounted for," police spokesman Det Cruz Hernandez said.
The tornadoes follow several days of freak weather in the southern United States, where heavy rain and flooding have left at least 17 people dead in Mississippi, Tennessee and Arkansas.