Updated

Swiss authorities said Friday that the Netherlands arrested and expelled two suspected Russian spies who allegedly tried to hack a Swiss laboratory that conducts tests for the U.N.-backed chemical weapons watchdog.

Switzerland's foreign ministry summoned the Russian ambassador to protest the attempted attack.

The Federal Intelligence Service says it worked "actively" with British and Dutch partners on the case involving Switzerland's Spiez Laboratory. Russia's foreign minister said earlier this year that the lab analyzed samples linked to the poisoning of former Russian spy Sergei Skripal and his daughter in England.

The 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.

"The Swiss authorities are aware of the case of Russian spies discovered in The Hague and expelled from the same place," said FIS spokeswoman Isabelle Graber in an email. "The Swiss Federal Intelligence Service participated actively in this operation together with its Dutch and British partners."

"The FIS has thus contributed to the prevention of illegal actions against a critical Swiss infrastructure," she added, while declining to comment further.

The Swiss attorney general's office confirmed it had identified "two individuals" as part of a broader investigation opened last year.

Switzerland's foreign ministry said it summoned Russia's ambassador on Friday to "protest against this attempted attack" and demanded that Russia "immediately" end its spying activities on Swiss soil.

Andreas Bucher, a spokesman for the laboratory, declined to comment on the expulsions, but added: "We have had indications that we have been in the crosshairs of hackers in the last few months." He said the lab had taken precautions, and no data was lost.

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," he was quoted as saying, alluding to the events that took place six months ago. "We have seen this article and it gives rise to a lot of questions ... It is absurd, just new groundless allegations."