FBI Assistant Special Agent Dennis Lormel said while there is still a concern over the chemical being used in a terrorist act, the probe is now focusing on ammonium nitrates two main uses as a mining explosive or an agriculture additive.
To this date, it points in the other direction. Were focusing on other areas, which would lead back to agricultural or commercial use, Lormel said.
The odorless, white pellets are a variety of ammonium nitrate normally used as a commercial blasting agent; they can also be used as a fertilizer.
The chemical was discovered missing from a storage bin at Bruceton Farm Services in Preston County, just east of Morgantown near the Pennsylvania border.
The FBI has offered a 10,000 reward for information leading to an arrest and prosecution, but Lormel said few people have responded with information.
He said most of the leads have been generated by interviewing area residents. That probe has now been expanded into rural neighboring areas of Pennsylvania and Maryland.
The ammonium nitrate was discovered missing on July 28 but had not been accounted for since June 19, a time span that Lormel said is hampering the investigation.
Unfortunately, that window of opportunity, coupled with the lack of security and accountability at the plant, has hamstrung us, Lormel said. Were trying to narrow the time frame and leads as best we can.
He said the lax security at the plant, which sells primarily to mining companies, was amazing, considering the potential.
Ammonium nitrate was a key part of the bomb used to destroy the Alfred P. Murrah Federal Building in Oklahoma City in 1995, killing 168 people and wounding hundreds of others.
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