GRANITE CITY, Ill. (AP) -€” Investigators are still trying to determine how a live mortar shell ended up at a recycling plant in southwestern Illinois where it exploded and killed two people this week.

Totall Metal Recycling in Granite City receives some material from the U.S. military, including spent shell casings.

But company spokeswoman Rebecca Rausch tells the Belleville News-Democrat (http://bit.ly/1vmzUsa ) that under that contract, shipments are not supposed to include live ammunition.

The village president of nearby Fairmont City, Alex Bregen, called Monday’s explosion a “terrible accident” and said one live shell out of hundreds of thousands sent to the plant “slipped through the cracks.”

The Bureau of Alcohol, Tobacco, Firearms and Explosives is handling the investigation.

The victims were identified as 46-year-old Rodolfo Romo of Fairmont City and 24-year-old Tyler Muenstermann of Edwardsville.

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