CHICAGO, United States (AFP) – Rare December tornados knocked cars off a highway and flattened homes in Texas, bringing the death toll to 25 in days of storms tearing across the southern United States.

The extreme weather, fueled by unseasonably warm air, is likely to continue for the next few days, the National Weather Service reported, snarling  holiday travel across a large section of the country.

The late Saturday deaths in Texas came as millions of residents in the southern United States struggle to recover from fierce storms and heavy flooding, with more rain in the forecast.

At least 17 people were killed in storm-related incidents since Wednesday in Mississippi, Tennessee and Arkansas, local officials said.

At least eight people were killed as tornados touched down in parts of the densely populated Dallas-Fort Worth metroplex, local officials and media reported.

A twister struck around 6:45 pm (0045 GMT Sunday) in Garland, Texas, city officials said in a statement.

“Five deaths have been confirmed,” the statement said. “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,” it said, adding that there was also an unconfirmed number of injuries and that teams of rescuers are arriving to help scour damaged areas.

The tornados snapped power cables and knocked over pylons, leaving some 30,000 Garland residents in the dark, the city said.

The Garland fatalities were apparently “blown off the highway by high winds,” Garland police spokesman Mike Hatfield told the Dallas Morning News.

“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.

Local TV weather reporters said that 11 twisters touched down in the region, a figure the NWS was unable to immediately confirm.