At least eight people were killed as tornados struck parts of northern Texas, leaving much of the region in the dark, local officials and media reported late Saturday.

A tornado touched down around 6:45 pm (0045 GMT Sunday) in Garland, Texas, part of the vast Dallas-Fort Worth metroplex, city officials said in a statement.

"Five deaths have been confirmed," read the Garland statement. "Extensive damage has been reported to vehicles, homes, and apartments in the same area."

The deaths are "believed to be related to vehicles struck by the tornado," the statement read, adding that there was also an unconfirmed number of injuries.

The tornados -- residents say at least four of them -- ripped off power cables and knocked over pylons, leaving some 50,000 people in the dark, the Dallas Morning News reported.

The Garland fatalities were apparently "blown off the highway by high winds," Garland police spokesman Mike Hatfield told the newspaper.

"We're dealing with darkness out here," Hatfield said. "All of the street lights and highway lights are out."

Three other people were killed in weather-related incidents in Collin County, just north of the metroplex, the newspaper said, citing local police.

Saturday's tragedy comes as millions of residents in the southern United States struggle to recover from fierce storms and floods that officials say have left at least 17 people dead in Mississippi, Tennessee and Arkansas.

With more severe weather expected across the central United States, forecasters are warning of airport delays and flooded roads as travelers return home after the Christmas holiday.