Sen. Robert Menendez (D-NJ) has been indicted in New York on federal corruption charges, The New York Times reported on Friday — the second time in a decade he has faced such a criminal prosecution.

"The indictment against Mr. Menendez, a 69-year-old Democrat who leads the Senate’s Foreign Relations Committee, follows a lengthy investigation by federal prosecutors in Manhattan," reported Benjamin Weiser, Tracey Tully and William K. Rashbaum. "It has been known for some time that Mr. Menendez was under federal scrutiny, and he has said he was willing to assist investigators and was confident the matter would be 'successfully closed.'"

The criminal investigation, which was first reported last year, has focused on whether he and his wife, Nadine Arslanian, traded gifts for political favors in the capacity of his legislative office. Prosecutors also looked into how a New Jersey businessman who met with Menendez was selected as the sole certifier of Halal meat exported from the United States to Egypt.

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Also among the oddities prosecutors were investigation were how Arslanian sold $40,000 in gold bars immediately before the corruption probe started.

Menendez, who has maintained he did nothing illegal, was previously indicted in an unrelated corruption probe in 2015. In that case, prosecutors alleged that he improperly accepted $1 million in gifts and campaign contributions from Florida opthalmologist Salomon Melgen, in exchange for expediting visas for his multiple girlfriends and resolving a Medicare billing dispute in his favor.

That case ended in a mistrial after the jury deadlocked, and the DOJ ultimately dropped the charges rather than bring the case again.