WALDORF, Md. (AP) — Federal authorities are offering a $10,000 reward for an arrest in two Charles County arsons in one week.

The U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives says they’re taking the fires at the Spirit Halloween store and Fred’s Sporting Store in Waldorf “very seriously.”

The first fire came Oct. 13 at Fred’s, a gun range, and caused about $1 million in damage. The store also had been robbed.

Exactly a week after that on Oct. 20, someone set fire to the Spirit Halloween store, next door to the gun range. That fire caused about $500,000 in damage before firefighters put it out. There was no evidence of robbery at that store.

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