The ANSA news agency reported the cash, along with an unspecified among of drugs and weapons, were taken from the Perreca-Delli Paoli clan, which operated in the area north of Naples and was associated with the Casalesi clan.
ANSA said the Casalesi clan's death threats led to anti-Mafia writer Roberto Saviano being placed under police protection.
Police said helicopters aided with the operation, which targeted two notorious drug-trading districts in Naples.
Friday's operation follows a confiscation that took place Dec. 13 in which police seized assets worth 35 million euros ($46.1 million).
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