Officials have not ruled out the role of an intruder or other criminal activity being involved. Ten first responders and two people volunteering to help fight the initial fire died in the explosion.
Matt Cawthon, the chief deputy sheriff in McLennan County, said in an interview Friday that anhydrous ammonia theft calls had declined in recent years, as had the number of meth labs authorities have busted as Mexican drug cartels are smuggling in more of the drug.
“The thefts … and the reports for law enforcement assistance in that area, in my estimation, were minor and were petty,” Cawthon said.
There were no reports that ammonium nitrate had been stolen from the plant, Cawthon said.
“If ammonium nitrate had been stolen … then that report would have generated probably a lot of attention,” he said.
Federal regulation of ammonium nitrate is largely focused on the safe storage of the chemical, for fear it will fall into the hands of criminals or terrorists. The U.S. Department of Homeland Security is responsible for oversight of the potentially explosive substance.
At the West facility, criminals appeared to be interested in the ammonia.
A West police officer in 2002 pulled over someone driving through West Fertilizer with his vehicle’s headlights off, according to a sheriff’s crime report. The police officer reported that “there have been numerous thefts of anhydrous ammonia” from the plant, the report says. But that driver was found to have taken a hydraulic hay spear.
That same year, a plant employee told authorities that someone was stealing 4 to 5 gallons of anhydrous ammonia about every three days, according to another report. Sheriff’s office records released Friday did not indicate that authorities were being called that often.
In more recent calls, an employee had noticed signs that someone had gone through the office without taking anything. In one 2009 record, someone reported that the TV in the office was left on a Spanish-language channel. The year before, an intruder appeared to have viewed pornography on a secretary’s computer.