WEST, Texas — Investigators have completed their work in the remnants of an exploded Texas fertilizer plant but have not ruled out criminal activity as the cause of a massive explosion that killed 15 people and flattened part of a tiny Texas town, officials said Thursday.
Officials have spent one month combing through debris and speaking to hundreds of witnesses since the April 17 blast at West Fertilizer injured 200 and leveled part of the town of West.
"At this time, the State Fire Marhsal's Office and ATF are ruling the cause of the fire as undetermined," State Fire Marshal Chris Connealy said at a news conference. He said officials had briefed victims' families earlier with the hope of giving them some degree of closure.
Authorities have ruled out the possibility that the blast was an act of terror, but not that it was a crime. A criminal investigation continues.
Investigators narrowed the number of possible causes to three: a problem with one of the plant's electrical systems, a battery-powered golf cart or a criminal act.
The golf cart was parked in the room where investigators think the blast began and had been recalled by its manufacturer. All that was found of it were a brake pad and an axle.
A golf cart's batteries hold a charge and when they fail, they can ignite the materials around them, officials said.
Authorities refused to take questions on the arrest of Bryce Reed, a paramedic who responded to the blast. Reed pleaded not guilty Wednesday to a charge he possessed bombmaking materials, but authorities stressed again Thursday they have nothing linking Reed to the blast.
Rachel Moreno, a spokeswoman for the Texas State Fire Marshal's Office, said the death toll officially reached 15 with the determination by a local justice of the peace that an elderly man who died after being evacuated from the nursing home had been an explosion-related death.