NEW ORLEANS (AP) - A town in northwest Louisiana was being evacuated and state police were starting a criminal investigation of a company after finding about 6 million pounds of explosive material they say was stored illegally.

State police superintendent Col. Mike Edmonson said Sunday that boxes and small barrels of the M6 artillery propellant were found both outdoors and crammed into unauthorized buildings leased by Explo Systems Inc. at Camp Minden, a former Army ammunition plant.

Police are evacuating the town of Doyline. About half the town's 800 residents left Friday.

M6 propellant is used in howitzers and other artillery. Police began investigating the company after an explosion at the site Oct. 15.

Doyline was used to film some scenes for the HBO vampire series "True Blood."

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