A woman and child were found dead from carbon-monoxide poisoning in Texas after using their car to generate heat amid power outages from a rare winter storm

• Houston police said early Tuesday that a woman and a girl had died from carbon-monoxide poisoning.
• The department said on Twitter that the family was using a car to generate heat after losing power.
• A man and a 7-year-old boy at the home were also treated for carbon-monoxide poisoning.

A woman and an 8-year-old girl were found dead from carbon-monoxide poisoning in Houston early Tuesday after using their car to generate heat amid power outages from a rare winter storm that battered the South over the weekend.

The Houston Police Department said on Twitter that officers were carrying out a wellness check and found the woman, the girl, a man, and a 7-year-old boy.

"Initial indications are that car was running in the attached garage to create heat as the power is out," the police said. "Cars, grills and generators should not be used in or near a building."

The police told ABC 13 that the woman was found dead in the car and that the girl was found dead in a condo attached to the garage.

The man and the boy were taken to a nearby hospital and treated for carbon-monoxide poisoning, the police said.

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Officers said that the woman had been speaking to a relative in Colorado on the phone when she passed out and that the relative called the police to request the wellness check.

"It's a very difficult time. A lot of people are without power," Lt. Larry Crowson told ABC 13. "I know it's cold, but you've got to be careful about using generators or cars inside a garage, or any type of fire, grill or charcoal grill. Carbon monoxide is odorless and can kill people very easily."

Temperatures in Texas ranged from negative 8 degrees Fahrenheit in Eastland to 5 degrees Fahrenheit in Fort Hood early Tuesday, and millions of homes experienced power outages.

The extreme cold blast is predicted to affect the power grid in Texas and other Southern states through Tuesday.

Law-enforcement officials suggested that a man who was found dead on a median in central Houston and a 60-year-old homeless man who was found dead in a van on an overpass had likely died from exposure to the freezing conditions.

At least six people died in a 130-vehicle pileup on an icy highway in Fort Worth on Thursday.