TURNER – Investigators are trying to determine the type of liquid fuel igniter that was used in a wood stove, causing a fireball that claimed the life of a 7-year-old boy in Turner.

Maine Fire Marshal John Dean said the flames blew back on three boys and ignited the clothes of Riley Davis, who died Sunday after suffering burns over 70 percent of his body. His cousins, 8-year-old Bradi Birney and 11-year-old Brandon Birney, also were burned.

It initially was reported that the boys used diesel fuel to start the fire in a wood stove in the basement of an enclosed foundation next door to the family’s home.

But Dean says the explosion was likely too intense to have been caused by diesel. His office is conducting tests to determine what fuel the children used.