Japanese police said today they were investigating a suspected group suicide involving seven people who met through the Internet.
The four men and three women, mostly in their twenties, were found dead today in a car parked on a mountain road in Minano in Saitama prefecture near Tokyo, officers said.
Police said they found four charcoal stoves in the car, which was wrapped in blue plastic sheets and had its windows sealed from the inside.
"We believe they all died after inhaling carbon monoxide from the charcoal," a police spokesman said. "We believe they got acquainted through the Internet."
One of the seven had sent an e-mail to a friend yesterday saying he would commit suicide, the spokesman said.
Empty cans of liquor were found inside the car and a box of sleeping pills near the silver vehicle, Kyodo news agency said.
Elsewhere, in Kanagawa prefecture, just west of Tokyo, police said two women in their twenties had killed themselves in a car in what was believed to be another case of "Internet suicide".
Cases dubbed by the Japanese media as "Internet suicide" pacts started to come to the fore in 2003. A total of 34 people killed themselves in such pacts last year, according to police data.
No religious prohibitions exist in Japan against suicide and it has long been seen as a way to escape failure or of saving loved ones from embarrassment for financial loss. However, it has also been stigmatised as a shameful, taboo subject.