By Nate Raymond and Thomas Atkins
NEW YORK/FRANKFURT (Reuters) - A former Swiss banker charged by U.S. prosecutors with helping wealthy Americans evade taxes has been arrested in Germany pending extradition to the United States, his lawyer said on Saturday.
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 (787 million pounds) in assets.
Thomas Green, Keller's lawyer at the law firm Sidley Austin, in an email Saturday confirmed that his client had been arrested and is being held in Germany pending his extradition.
"I have not yet been in contact with Roger, but hope that can be arranged soon," Green said.
The case is one of a number spilling out of a broad crackdown by the United States on offshore tax evasion by Americans.
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.
The bank was indicted a month after U.S. prosecutors announced charges against Keller and two other Wegelin bankers, Michael Berlinka and Urs Frei. All three were from Switzerland, which does not extradite its own citizens.
Alexander Badle, spokesman for the general prosecutor's office in Frankfurt, in a statement Saturday said a 50-year-old Swiss citizen was arrested at the Frankfurt Airport due to an international arrest warrant from the United States.
Badle declined to provide the name of the Swiss citizen. Keller had been 47 at the time U.S. charges were announced in January 2012.
"The subject remains in custody due to a detention order," Badle said. "No decision on extradition has been made."
A spokesman for Manhattan U.S. Attorney Preet Bharara, whose office announced the indictment, declined comment.
The arrest comes as authorities in the United States continue to probe the role of a handful of other Swiss banks in helping wealthy Americans avoid paying taxes.
Credit Suisse Group AG (VX:CSGN) in 2014 pleaded guilty to conspiracy to aid and assist U.S. taxpayers in filing false returns as part of a more than $2.5 billion settlement with several government authorities.
In 2009, UBS AG agreed to pay $780 million as part of a deferred prosecution agreement resolving charges it defrauded the United States by impeding the Internal Revenue Service.
The case is U.S. v. Berlinka, et al, U.S. District Court, Southern District of New York, No. 12-cr-00002.