CASTAIC -- A woman whose body was found inside a car in a remote area near Castaic was likely the victim of hydrogen sulphide gas poisoning, commonly known as "detergent suicide," investigators say.

The woman's body was found slumped in the back seat of a blue Honda Civic about 9:40 a.m. near Lake Hughes Road and Dry Gulch Road on Tuesday, according to L.A. County Fire Inspector Matt Levesque.

A pair of deputies who were on a routine patrol of the area spotted the vehicle in a dirt area off the road, Levesque said.


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Deputies approached the car and saw a person inside the vehicle "slumped over the back seat and not moving," according to L.A. County Sheriff's spokesman Steve Whitmore.

The windows of the vehicle was covered with stickers that read 'Stay Away." "Dangerous Gas," and "Don't Open," according to L.A. County Sheriff's spokesman Steve Whitmore.

According to Sheriff's Department Spokesman Steve Whitmore, a female was found deceased in the car.

Investigators believe that hydrogen sulphide gas was present, and that discovery prompted a long and careful clearance procedure by LA County HAZMAT teams.

Hydrogen sulfide gas can be made by mixing store-bought detergents and chemicals.

The gas almost always kills and sometimes the victims of the poisonous fumes are passers-by or rescue personnel.

The process, known as 'detergent suicide' is a popular method of suicide particularly in Japan.

It is a common practice for victims to post warnings for rescuers of the presence of the toxic gas.

In Japan in the first half of 2008, more than 500 people committed suicide by mixing a bath sulfur, something unavailable in the United States, with a toilet bowl cleaner to create hydrogen sulfide, according to published reports.

In the United States, other common cleaning chemicals are substituted for bath sulfur to make the gas, and one of the first so-called detergent suicides occurred in Pasadena in 2009.

Deputies learned the 20-year old woman had been reported missing and was last seen Sunday.