An insurance company is offering a $50,000 reward to help find a masked man in a full-length black gown who stole more than $1 million in diamonds from a Hawaii jewelry store on Halloween.

Maui police say the gowned and masked man also wore black gloves to rob Greenleaf Diamonds in Lahaina at gunpoint.

Police say there were no customers inside when he brandished the pistol and demanded three items from the display case. Police say he stole a pink diamond valued at $240,000, diamond stud earrings valued at $378,000 and a platinum “fancy light pink” diamond valued at $450,000.

Jewelers Mutual Insurance Company is offering the reward for information that leads to an arrest and conviction. The company will also pay 10% of the cost of any merchandise recovered through information provided.

(AP)