(Photo courtesy of the Pinal County Sheriff's Office)

Brittany Velasquez, 20, has been charged with two counts of first-degree murder in the deaths of her 2-year-old son and 2-month-old daughter.

A mother in the town of Superior has been accused in the deaths of her two young children. Brittany Velasquez, 20, faces two charges of first-degree murder.

The investigation is being handled by the Pinal County Sheriff’s Office, which was alerted Monday night after Velasquez called 911. Sheriff’s Office Spokesperson Navideh Forghani said a 2-year-old-boy and 10-month-old girl were dead when authorities arrived at the suspect’s home, about 65 miles east of Phoenix.

“Both of the children were actually strapped in to their car seat in the back of a car when they were found,” she said. “Our detectives did find some signs of foul play.”

Forghani said she could not give details at this time, but the evidence was strong enough to charge Velasquez in the deaths.

Initial autopsy results could be available soon, Forghani said, but final results could take months.