Berlin - German investigators say six teenagers whose bodies were found at a garden house in Bavaria died of carbon monoxide poisoning.
Wuerzburg prosecutors and police said on Tuesday they still are working to determine the source of the gas and what caused it to leak.
Investigators have said a wood-fired stove was in use at the house.
The owner of the garden in Arnstein, around 75km east of Frankfurt, found the bodies of his son, daughter and four other young men on Sunday morning. All were aged 18 or 19.
He went to the house after failing to reach his children, who had held a party there on Saturday night. Investigators ordered autopsies and blood tests on the bodies.