Germany summoned the U.S. ambassador Friday over allegations that a suspect arrested this week spied for the United States.
The Foreign Ministry says it asked Ambassador John B. Emerson to help with what it calls the "swift clarification" of the case.
The German Federal Prosecutor's office said in a statement that a 31-year-old man had been arrested on suspicion of being a foreign spy, but it gave no further details.
German authorities say a man was arrested Wednesday on suspicion of spying for foreign intelligence services.
They did not identify the suspect or for which governments he spied.
But German newspapers say he worked for German intelligence and passed information to the U.S. on a parliamentary committee investigating U.S. intelligence activities in Germany.
German and U.S. officials have not commented on the reports, but Chancellor Angela Merkel has been informed about the arrest.
Germany has been suspicious about U.S. intelligence activity since documents leaked by former U.S. contractor Edward Snowden showed the U.S. spied on German citizens and listened in on Merkel's cellphone.
Cahrges of passing information
The man has admitted passing to an American contact details about a special German parliamentary committee set up to investigate the spying revelations made by Snowden, politicians said.
“This was a man who had no direct contact with the investigative committee ... He was not a top agent,” said one of the politicians, who spoke on condition of anonymity.
The suspect had offered his services to the United States voluntarily, the source said. The United States embassy in Berlin declined to comment.
Germany is particularly sensitive about surveillance because of abuses by the East German Stasi secret police and the Nazis. Berlin has demanded that Washington agree to a “no-spy” with its close ally, but the United States has been unwilling.
Bild newspaper said in an advance copy of an article to be published on Saturday that the man had worked for two years as a double agent and had stolen 218 confidential documents.
He sold the documents, three of which related to the work of the committee in the Bundestag, for 25,000 euros ($34,100), Bild said, citing security sources.
Some information for this report was supplied by Reuters.