U.S. authorities arrested 48 people in three U.S. states as part of a previously undisclosed campaign against Mexico's Sinaloa drug trafficking cartel, a law enforcement official said on Wednesday.

Wednesday's sweep in California, Maryland and Minnesota brought to 751 the total number of arrests under "Operation XCellerator," begun nearly two years ago, the official said. Some 20 tons of illegal drugs, including cocaine, marijuana, methamphetamine and Ecstasy have been seized.

U.S. officials have voiced increasing concern over violence and corruption in Mexico linked to the cartels. The traffickers are accused of using proceeds from drug sales in the United States to smuggle into Mexico weapons used in deadly turf battles.

Former CIA chief Michael Hayden said in January before he stepped down that instability in Mexico linked to the drugs violence was a potential near-term threat to U.S. security.

Suspects indicted as part of operation against the Sinaloa cartel faced charges of racketeering, drug smuggling, money laundering and illegal weapons possession, the officials said.

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