The Dallas County medical examiner confirmed Thursday that the victims were Caleb Furley and his son, Andres. The cause of death had not been determined as of Thursday, and investigators have not said what led to their deaths.

Andres’ mother was scheduled to pick him up at Furley’s Norman home Monday. When the two could not be located, Norman police received a call at about 11 p.m. and began an investigation. Capt. Lee McWorther said detectives’ findings led them to believe both father and son could be at risk. An Amber Alert was issued, and a child-stealing charge followed.

On Wednesday morning, Gainesville police received a report from one of Furley’s relatives, who said a man and child matching their description had been seen at a local store Monday afternoon in what the caller considered a suspicious encounter. Investigators reviewed surveillance footage in the area and found the bodies, McWorther said.

An arrest warrant cited concerns raised by Furley’s mother and Andres’ mother about his mental health. McWorther said Furley’s mother reported that he had been seeing someone for help but had stopped. Authorities have not identified that as a cause of the deaths.

Furley was a senior studying computer science at the University of Oklahoma. The university said it was cooperating with law enforcement and offered condolences to the family and others affected. The investigation is ongoing.