TIMONIUM, Md. — Baltimore County Police have arrested two vendors they say sold illegal high-capacity magazines at a gun show at the Timonium Fairgrounds.

Officers say an undercover detective saw a vendor sell what appeared to be a 30-round magazine at the show on Friday. Maryland law prohibits buying or selling magazines over 20 rounds.

Police talked with the customers and seized the item.

Police say the detective then went to the vendor and asked to buy a 30-round magazine. Officers say the detective bought two magazines, which were labeled as holding 20 rounds.

Authorities say the items were 30-round magazines. Police say they recovered 121 additional illegal magazines from the vendor stand.

Fifty-seven-year-old John Heilmeier of Cumberland, Va., and 64-year-old Richard Summers of Waldorf were each charged with a firearms violation.

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