By Nate Raymond

(Reuters) - A Washington lawyer from a major law firm was wearing a wig as a disguise when he was arrested last week trying to sell a copy of a secret lawsuit against a California technology security company for $310,000, according to a criminal complaint.

Jeffrey Wertkin, a former U.S. Justice Department trial attorney who joined Akin Gump Strauss Hauer & Feld LLP as a partner last year, was charged in the complaint filed in federal court in San Francisco made public on Tuesday.

He was arrested on Jan. 31 at a Cupertino, California, hotel while trying to sell a copy of the lawsuit to an FBI agent posing as a colleague of an employee at the security firm in exchange for a duffle bag full of money, the complaint said.

"My life is over," Wertkin said out loud shortly after his arrest by the Federal Bureau of Investigation, according to the complaint, which did not state where he obtained the lawsuit filed under the False Claims Act.

A lawyer for Wertkin, who was charged with contempt of court, could not be immediately identified. Akin Gump in a statement said it was "shocked and deeply troubled by the conduct alleged in the charges filed against Mr. Wertkin."

"Immediately upon learning of these charges, we took swift action and Mr. Wertkin is no longer with the firm," Akin Gump said.

According to the complaint, the lawsuit was filed in January 2016 under the False Claims Act, which allows whistleblowers to sue companies on the government's behalf to recover taxpayer money paid out based on fraudulent claims.

Those lawsuits are filed under seal to allow the Justice Department to investigate and determine whether it wants to intervene in the cases. Whistleblowers can receive a share of any resulting recovery.

Wertkin joined 920-lawyer Akin Gump in its Washington office in April 2016 from the U.S. Justice Department, where he was involved in pursuing False Claims Act cases and several fraud investigations as a trial attorney, the complaint said.

According to the complaint, in November, someone calling himself "Dan" contacted an employee of the Sunnyvale, California-based security company to discuss providing a copy of the lawsuit for a "consulting fee."

That employee began recording calls with "Dan" at the FBI's request, and negotiated to have a colleague, who was actually an agent, deliver $310,000 in exchange for the lawsuit.

The case is U.S. v. Wertkin, U.S. District Court, Northern District of California, No. 17-mj-70131.

(Reporting by Nate Raymond in New York; Editing by Andrew Hay)