Four kids are dead after an apparent accidental gas poisoning involving a professional-grade pesticide at a home in Amarillo, Tex.

Fire officials have not released an official cause of death on the matter, but they believe phosphine gas was the cause. They believe the lethal gas was released when water was sprayed around the house mixing with pesticide pellets called Weevil-cide, which is only supposed to be sold to people with professional licenses or certification.

The father of the children who died told first responders that he had gotten the pesticide pellets from a friend and spread them under the mobile home. The product's manual says that the pellets are only for use in the commercial transport and storage of commodities and animal feed.

Fire officials arrived on the scene believing it to be carbon monoxide poisoning, but that was quickly ruled out. Ten people in total were in the house. One child died at the scene and another three died later in the hospital. The other six are currently still in the hospital and a fire official says 'they're not out of the woods yet'.

Officials didn't release any identifying information, including the children's ages or whether they were related. Amarillo fire Captian Larry Davis said all four people who died were residents of the home.

A criminal investigation is now underway to determine whether charges will be filed.

Davis told the Amarillo Globe-News he wasn't sure how long the residents had been exposed to the phosphine gas before a visitor arrived Monday and found everyone sick and called 911. Police and fire officials were also taken to the hospital as a precautionary measure, but none of them have shown symptoms of the gas.

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