A criminal investigation has been launched into the West,Texas fertilizer plant that exploded last month.

The Texas Department of Public Safety says it directedthe Texas Rangers to join the McLennan County Sheriff inan investigation of the circumstances surrounding the massiveexplosion of West Fertilizer Co. on April 17.

“This disaster has severely impacted the community of West,and we want to ensure that no stone goes unturned and that allthe facts related to this incident are uncovered,” said DPSDirector Steven McCraw, in a statement. “The citizens of McLennanCounty and Texas must have confidence that this incident hasbeen looked at from every angle and professionally handled.”

DPS says its Division of Emergency Management continuesto work with local, state and federal authorities toassess damages and facilitate recovery assistance to thevictims.

Meanwhile, Reuters reports a paramedic in West, Texas, hasbeen arrested by federal officials for possession of an explosivedevice, but it was unclear whether there was in connection to theexplosion last month at a fertilizer plant in the town, a sourcefamiliar with the matter said on Friday.

Blog: Doesn't Matter How West Fertilizer Dangers WereRevealed

Investigators confirmed ammonium nitrate was thetrigger for the explosion at the fertilizer retailer that left 15people dead and about 200 injured.

The West Fertilizer Co. carried $1 million in liability insurance provided byUnited States Fire Insurance Co., a member of Morristown,N.J.-based Crum & Forster, which is part of the Fairfax Group.A spokesman for Adair Grain Inc., the parent company of WestFertilizer, says the company did not have excess or umbrellacoverage.

The Texas Department of Insurance says four state agencies withsome oversight of these types of facilities—State Health Services,Texas State Chemist, Texas Commission on Environmental Quality, andTexas Agriculture Department—do not require general liability aWest Fertilizer-type operation.

The Insurance Council of Texas estimates insured property losses are $100 million. The totalincludes estimated insurance payments for the plant, 140 homes, anapartment complex, a middle school and a retirement center.

Several lawsuits have been filed against Adair Grain since theforce of the April 17 blast leveled or damaged a large swath of thesurrounding town. Multiple companies within the W.R. Berkley Corp. group of insurers are among those who have filedsuit, claiming negligence on the part of the Adairs.

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