NEW YORK (AP) — U.S. Rep. Michael Grimm has been indicted on mail, wire and tax fraud charges, but he says the case is trumped up.

The Staten Island Republican was arrested Monday and pleaded not guilty to a 20-count federal indictment. He has been released on $400,000 bail.

Grimm says the government framed him. He says investigators couldn't make a campaign finance case against him stick, so they trumped up the fraud accusations.

He says he is the victim of a "political witch hunt."

Grimm is charged with engaging in schemes to underreport wages for restaurant workers, including some who were in the country illegally. He is accused of concealing more than $1 million in sales and wages.

Grimm is a former FBI agent who left the bureau in the mid-2000s. He was elected in 2010.

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