A woman and 8-year-old child, who used a car to generate heat and keep warm amid the winter storm in Texas, died of carbon monoxide poisoning. Another man and a child, who were also affected by the poisoning, were hospitalized.

Officers with the Houston Police Department arrived at the home for a welfare check and found four people "affected by carbon monoxide poisoning."

"Mid West officers and HFD were dispatched to 8300 La Roche on a welfare check. Upon making entry they found two adults and two children affected by carbon monoxide poisoning," the police said in a statement Tuesday.

While the woman and 8-year-old girl were pronounced dead at the scene, the man and another child, reported to be 7 years old, were rushed to the hospital. Their condition was not known.

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

The woman was reportedly sitting in the running car while talking to a relative on the phone when she became disoriented and lost consciousness. The worried relative then contacted the police department, ABC 13 reported, quoting authorities. It remained unclear how the four victims were related. 

Carbon monoxide is found in fumes produced when one burns fuel in cars or trucks, engines, stoves, grills, fireplaces or furnaces. Carbon monoxide poisoning occurs when the gas builds up in your bloodstream, and the symptoms include headache, nausea, fatigue, blurred vision, and muscle aches.

The incident comes shortly after three children and their grandmother died after using a charcoal grill to heat their Houston apartment. Another adult and a child were in critical condition as of Monday night.

Speaking about the incidents, Lt. Larry Crowson said, "It's a very difficult time. A lot of people are without power. 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."

Harris County in Texas alone saw over 300 carbon monoxide poisoning cases as a winter storm pummeled the state and caused widespread power outages, sending residents scrambling for heat sources.

Pike Electric service trucks line up after a snow storm on February 16, 2021 in Fort Worth, Texas Pike Electric service trucks line up after a snow storm on February 16, 2021 in Fort Worth, Texas Photo: GETTY IMAGES NORTH AMERICA / Ron Jenkins