A 17-year-old was found dead at the scene and three other children were transported to an area hospital where they later died, the Amarillo Globe-News reported.
The pesticide that was used contained aluminum phosphide, a chemical that, when mixed with water, creates phosphine gas, the newspaper said, citing local fire officials.
“This family may have been exposed to this for several days,” Amarillo Fire Department Captain Larry Davis told local TV station KDFA.
Names of the victims were not released, and Amarillo fire officials were not immediately available for comment.
There were five other people exposed to the gas who were in stable condition at an Amarillo hospital, the newspaper said citing fire officials. One other patient was transferred to a hospital in the Texas Panhandle city of Lubbock, and there was no information on the status of that person.
(Reporting by Jon Herskovitz; Editing by David Gregorio)