WEST, Texas (AP) — Investigators have not ruled out criminal activity as the cause of a massive explosion at a fertilizer plant that killed at least 14 people and flattened part of a tiny Texas town, two officials familiar with the findings said Thursday.
The April 17 blast at West Fertilizer injured 200 and leveled part of the tiny town of West. Officials have spent one month combing through debris and speaking to hundreds of witnesses.
But they have not yet been able to pinpoint the cause, the officials said.
One state official who's seen a report on the probe and a second law enforcement official briefed on the findings told The Associated Press investigators are focused on a golf cart on the premises that had been recalled by its manufacturer, an electrical problem or possible criminal activity.
The state official said investigators were "light on definitive information" into the cause of the blast. The official declined to give more details until after authorities held a news conference to announce their findings.
The law enforcement official said the golf cart in question was sometimes parked at the place where the fire began, but investigators said they could not confirm the cart was parked there on the night of the blast.
Investigators had ruled out other possible causes, including smoking or a weather-related fire, the law enforcement official said.
"Science just takes you so far in this," the law enforcement official said. "And that's all you can do."
Both officials spoke on condition of anonymity because briefings were ongoing and they did not want to speak publicly before a scheduled news conference by state and federal authorities.
Officials have determined that ammonium nitrate exploded, but they do not know what started the initial fire or caused the explosion.
The dead included 10 first responders and two volunteers trying to fight the initial fire, which was reported 18 minutes before the blast. The explosion registered as a small earthquake, sent debris flying more than a mile away, and left a 93-foot-wide crater at the site of a fertilizer storage building on site.
That left investigators from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives and the Texas State Fire Marshal's Office with an investigation some compared to an archaeological dig. The agencies brought in dozens of agents to sift through remnants of the site, stacking any piece of debris that might be useful on blue tarps and hauling away the rest.
Two months before the explosion, the plant reported it had the capacity to store as much as 270 tons of ammonium nitrate, though how much was actually on site when the blast occurred is unknown.
Ammonium nitrate is a chemical used as a fertilizer that can also be used as a cheap alternative to dynamite. It was the chemical used in the 1995 Oklahoma City bombing.
The fire marshal's office had previously ruled out several possible causes for the initial fire, including another fertilizer stored on site, anhydrous ammonia; a rail car on the site that was carrying ammonium nitrate; and a fire within a storage bin of ammonium nitrate.
Daniel Keeney, a spokesman for Adair Grain Co., which owned and operated West Fertilizer, has said the company is cooperating with authorities, but declined to comment further.
Vertuno reported from Austin.