WHITE OAK, Pa. (AP) — Authorities have determined the cause of death of an elderly man and woman in a western Pennsylvania house fire last year, but questions remain about their deaths.

The Allegheny County medical examiner's office says 79-year-old Thomas Barnett and 75-year-old Panida Barnett died of smoke inhalation and carbon monoxide poisoning in the Dec. 28 blaze in White Oak.

But the medical examiner's office says the manner of death — whether it was homicide, suicide or accidental — remains undetermined.

Allegheny County police are still investigating.