Moscow quickly rejected the accusation, the latest Western claim about Russian spying and other acts of interference. This time, the alleged target was the Spiez Laboratory, which analyzed samples from the March poisoning of former Russian spy Sergei Skripal and his daughter in England.
The Swiss confirmation came after Dutch newspaper NRC Handelsblad and Swiss newspaper Tages-Anzeiger reported that two Russians suspected of being agents of military intelligence service GRU were kicked out of the Netherlands earlier this year as a result of a Europe-wide investigation.
Tages-Anzeiger said the two men were arrested in The Hague during the spring, but the exact location and timing were unclear. Switzerland's Federal Intelligence Service did not provide details, but said Friday it worked "actively" with British and Dutch partners on the case.
"The Swiss authorities are aware of the case of Russian spies discovered in The Hague and expelled from the same place," FIS spokeswoman Isabelle Graber said in an email. She said the agency helped prevent "illegal actions against a critical Swiss infrastructure," and declined further comment.
The Swiss attorney general's office said "two individuals" involved in the alleged hacking emerged during a broader investigation of alleged "political espionage" that was opened in March 2017.
Switzerland's Foreign Ministry said it summoned Russia's ambassador to "protest against this attempted attack" and demanded that Russia "immediately" end its spying activities on Swiss soil.
But Russia's top diplomat scoffed at the time it took for the case to come to public light.
"I cannot suppose that such an occurrence, in which the specialists of three Western countries participated, could remain out of the field of view of the mass media," Foreign Minister Sergey Lavrov told reporters after meeting with his German counterpart in Berlin, Russian news agencies said.
The Russian state news agency Tass quoted Stanislav Smirnov, a spokesman for the Russian Embassy in Switzerland, as calling the Dutch news report "absurd."
"We believe that this is a new anti-Russian bogus story made up by the Western media," Smirnov was quoted as saying. "It is absurd, just new groundless allegations."
The Dutch Defense Ministry declined to comment.
Dutch Prime Minister Mark Rutte announced in March that the Netherlands had expelled two Russian intelligence agents. The action came amid a wave of Western nations ejecting Russian diplomats to protest the poisoning of the Skripals.
Spiez Laboratory spokesman Andreas Bucher declined to comment on the events in the Netherlands, but said the lab had taken precautions and no data was lost.
"We have had indications that we have been in the crosshairs of hackers in the last few months," he said.
Bucher also wouldn't comment on whether the lab analyzed samples linked to the Skripal case, saying it was "contractually bound" to confidentiality in its work for the U.N.-supported Organization for the Prohibition of Chemical Weapons.
The chemical weapons watchdog has been involved in investigating the England poisoning and is based in The Hague. Lavrov said earlier this year that the Spiez lab had analyzed samples from the England poisoning investigation.
Mike Corder in Rotterdam, Netherlands and Jim Heintz in Moscow contributed to this report.
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