KARLSRUHE (REUTERS) - Germany's top public prosecutor said an investigation into suspected tapping of Chancellor Angela Merkel's mobile phone by US spies had so far failed to find any concrete evidence.
Revelations by former National Security Agency employee Edward Snowden that Washington carried out large-scale electronic espionage in Germany provoked widespread outrage - particularly the allegation that the NSA had bugged Merkel's phone.
Harald Range launched an official investigation in June, believing there was enough preliminary evidence to show unknown US intelligence officers had tapped the phone, although there was not enough clarity on the issue to bring charges.
On Wednesday he said, however, "the document presented in public as proof of an actual tapping of the mobile phone is not an authentic surveillance order by the NSA. It does not come from the NSA database.
"There is no proof at the moment which could lead to charges that Chancellor Merkel's phone connection data was collected or her calls tapped."
Range said neither a reporter for German news magazine Spiegel who presented the document, nor Germany's BND foreign intelligence agency, nor Snowden had provided further details to his office. The investigation continues, however.
The spying affair severely tested ties between Berlin and Washington, but Berlin's pleas for a "no-spy" agreement with the US came to nothing.
Snowden has sought refuge in Moscow.
Merkel's government has shied away from bringing him to Berlin to testify to a parliamentary enquiry into the espionage, fearing it would further damage relations with Washington.