Brentwood police said the masked suspect brandished a gun Sept. 25 at the Stop and Shop deli in Brentwood and demanded money, WCBS-TV, New York, reported Tuesday.
Police said the suspect fired off a shot into the wall, leading the clerk to brandish a large machete he grabbed from under the counter and chase the robber from the store.
The store owner said she purchased the machete about a month ago following a series of thefts.
Police are offering a reward of up to $5,000 for information leading to the arrest of the suspect, who was armed with a .22-caliber pistol.
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