Investigators are considering if carbon monoxide poisoning was responsible for the death of a teenager over Easter.
Alex Mitchell was found dead at a house in Cwmbran
The body of Alex Mitchell, 14, was found at an address in Cwmbran, south Wales on Good Friday.
Gwent Police have launched an investigation and are being assisted by the Health and Safety Executive.
The coroner has been informed of Alex's death and police are awaiting the results of a post mortem examination.
In a statement issued on Wednesday, Alex's family paid tribute to the teenager, describing her as "a wonderful most beautiful and talented granddaughter, daughter, sister and auntie".
"You've given us fourteen happy years of love, laughter and inspiration. Always an honour to have loved and shared with you, you'll be held in our hearts forever," said the statement by the Mitchell family.