Washington (CNN) -- One of the prosecutors who handled the corruption trial of Alaska Sen. Ted Stevens committed suicide over the weekend, according to his lawyer.

Justice Department prosecutor Nicholas Marsh and five others have been the subject of an investigation by the Justice Department's Office of Professional Responsibility over their handling of the Stevens case, which the Justice Department ultimately dropped amid charges the government did not properly share evidence with Stevens' defense attorneys. The judge in the Stevens case also ordered a special prosecutor to look into it.

Bob Luskin, an attorney for Marsh, told CNN Marsh killed himself but did not provide details. "It did seem he was overwhelmed by the emotional cost of this investigation," said Luskin. According to the attorney, Marsh was in his late 30s.

Luskin called Marsh's death "incredibly sad" and said the investigation was in its final stages and he expressed confidence no charges would have been brought against Marsh.

The Justice Department did not comment on the circumstances of Marsh's death. Lanny Breuer, assistant attorney general for the criminal division issued a statement saying, "Our deepest sympathies go out to Nick's family and friends on this sad day. The Department of Justice is a community, and today our community is mourning the loss of this dedicated young attorney."

The Stevens case was handled by U.S. District Judge Emmet Sullivan in Washington. A court spokesman issued a statement saying in part, "Judge Sullivan and his staff were extremely saddened and shocked to hear the tragic news of Mr. Marsh's death."

At the time of his death Marsh was still working at the Justice Department in the international affairs section of the criminal division, according to Luskin.

Republican Sen. Ted Stevens was convicted of lying on his Senate financial disclosure forms. The verdict was set aside, but not before he lost a close re-election contest in 2008. Stevens was killed earlier this year in a small plane accident in Alaska.