OCEAN CITY, Md. (AP) — Police in Ocean City say 23 people have been indicted on heroin charges as the beach resort deals with a spike in use of the drug.

Police say 17 are in custody and six are being sought. Officer Michael Levy says Ocean City has seen an increase of nearly 550 percent in heroin cases, compared with last year. Levy says investigators think the rise in heroin use is linked to an ongoing crackdown on prescription drug abuse. That is prompting prescription drug addicts to turn to illegal opiates and heroin is the cheapest and easiest to get on the street.

Authorities say the indictments announced Tuesday follow a six-week undercover investigation in which officers made about 72 drug buys.

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