Ammonium nitrate was explosive in plant blast

AUSTIN, Texas (AP) - A store of ammonium nitrate is what exploded April 17 at a Central Texas plant, killing 14 people, injuring hundreds and devastating an adjoining town.

The finding was expected, and officials had said they were focusing their investigation on the explosive chemical used in many fertilizers, said Rachel Moreno, spokeswoman for the Texas State Fire Marshal's Office. A spot where the ammonium nitrate was stored is now a 90-foot-wide crater, Moreno said Monday.

However, the ignition source for the explosive chemical remained undetermined Monday. Findings on the cause of the blast on the outskirts of the small town of West initially had been expected Friday. However, the investigation will take one to two extra weeks to complete, with dozens of investigators combing through plant wreckage and the adjoining wrecked neighborhood, Moreno said.

Also, federal emergency officials have begun offering shelter for West residents whose homes were destroyed or severely damaged. About 70 homes were damaged or destroyed.

A statement from the Federal Emergency Management Administration said the transitional sheltering assistance was requested by Texas state officials. It would allow those whose homes were left uninhabitable by the blast to stay for a limited time in a hotel or motel at government expense. Meals, telephone calls and other incidental charges are not covered, and applicants are responsible for any lodging costs above the authorized lodging costs, according to the statement. Eligible applicants are being notified.