Central California authorities arrested a 29-year-old man for allegedly intentionally starting a house fire that killed his 18-month-old niece and 5-month-old nephew and severely burned their mother.

The fire was reported early Tuesday in the San Joaquin Valley city of Fresno.

The 32-year-old mother, whose name was withheld, was “fighting for her life,” the Fresno Police Department said in a Facebook post Wednesday. She remained in critical condition Thursday, according to police Sgt. Diana Vega.

Police identified the niece as Cataleya Hurtado and the nephew as Calyx Hurtado. Their father was at work at the time of the fire.

The suspect, Filimon “Robert” Hurtado, was admitted to a hospital under guard because he also received “substantial” burns, the statement said.

He was charged Thursday with two counts of murder with special circumstances and one count of arson causing great bodily injury, the Fresno County District Attorney’s office said in a statement.

It was not immediately known if Hurtado had an attorney.

Police said he had no prior criminal history.

“When investigators interviewed the suspect, he made admissions to setting the house on fire because he wanted to kill everyone in the home,” the statement said. “He had no reasonable explanation as to why he committed this horrendous act.”