NEW YORK (Reuters) - A former Swiss banker who was arrested last year in Germany on U.S. charges that he helped wealthy Americans evade taxes is back in Switzerland after the denial of a request to extradite him to the United States from Germany, his lawyer said on Friday.

Roger Keller, a onetime client adviser in Zurich at Wegelin & Co, was one of three bankers at the now-defunct Swiss private bank charged in a 2012 indictment in New York federal court for helping U.S. taxpayers hide more than $1.2 billion in assets.

He was arrested in Germany in February 2015 at the request of the U.S. government, which sought his extradition, and served seven months in jail before being granted bail, said Thomas Green, Keller’s U.S. lawyer at the law firm Sidley Austin.

By German court order, he was officially released on Friday after the U.S. request to extradite him was denied, Green said, though Keller had already been allowed to return to Switzerland a “few days ago.”

Representatives for Manhattan U.S. Attorney Preet Bharara’s office, which had been prosecuting the case, had no immediate comment, nor did a spokesman for the general prosecutor’s office in Frankfurt.

The case against Keller is one of several brought by the U.S. Justice Department against Swiss bankers and their employers stemming from a U.S. crackdown on offshore tax evasion by wealthy Americans utilizing undeclared Swiss bank accounts.

Wegelin, Switzerland’s oldest private bank, was forced to close after agreeing in 2013 to plead guilty to conspiracy to evade taxes and pay $74 million.

Wegelin was indicted a month after prosecutors announced charges against Keller and two other Wegelin bankers. All three were from Switzerland, which the U.S. Justice Department has said does not extradite its citizens in such cases.

The U.S. Justice Department in January announced the final settlement in a program that resulted in 80 banks paying $1.36 billion to avoid prosecution. Some other banks also settled as part of U.S. criminal cases.

Those included UBS, which reached $780 million deferred prosecution deal in 2009; Credit Suisse, which as part of a plea deal in 2014 agreed to pay $2.6 billion; and Julius Baer, which in February agreed to pay $547 million in a deferred prosecution deal.

The case is U.S. v. Berlinka et al, U.S. District Court, Southern District of New York, No. 12-cr-00002.