Cause of West Explosion Undetermined
The possible causes of the blast have been narrowed to a failure in one of the plant's two electrical systems, a battery on a golf cart, or arson. Several other possibilities – including ammonium nitrate, spontaneous ignition, and smoking – have been ruled out.
The golf cart, which possibly had a recalled battery, could not be ruled out because the pieces had not been fully recovered. Authorities said that the blast destroyed 37 blocks, creating a 93 feet wide crater.
Officials are continuing the probe as a criminal investigation. Robert Champion, the Agent in Charge at the Dallas ATF office , however said "we will not speculate" on whether Bryce Ashley Reed was connected to the investigation. Reed, a former paramedic who helped victims following the explosion, was arrested for possession of a destructive device earlier this month. He later entered a not guilty plea.
According to investigators, there are no longer any missing persons.