ZURICH (Reuters) - Switzerland’s intelligence agency said on Friday it had worked with British and Dutch counterparts to foil a Russian plot which, according to newspaper reports, was targeting a Swiss laboratory testing nerve agents such as Novichok.

Earlier on Friday a Swiss and a Dutch newspaper reported that authorities from the three countries had teamed up in an operation which resulted in the Netherlands expelling two suspected Russian spies in March.

Citing unnamed sources, the Tages-Anzeiger and NRC Handelsblad reported that the suspected agents were heading for the Spiez laboratory near Bern which analyses chemical and biological weapons, including nerve agent Novichok.

Britain says Moscow used Novichok to try to kill former Russian spy Sergei Skripal in the English city of Salisbury in early March and last week charged two Russian men in absentia with attempted murder.

“Swiss authorities are aware of the case of Russian spies identified in The Hague and expelled from there,” the Swiss NDB intelligence agency said in a statement.

“The NDB took active part in this operation together with its Dutch and British partners. The NDB has thus contributed to preventing illegal activity targeting critical Swiss infrastructure.”

It did not elaborate.

The Russian embassy in Bern dismissed the Swiss account.

“We consider such false statements simply absurd and nothing other than another attempt to stoke an anti-Russian atmosphere,” it said.

The newspapers said the two suspects expelled from the Netherlands were not the same as the two men charged by British prosecutors in the Skripal case last week.

The Dutch military intelligence agency MIVD did not immediately respond to requests for comment. The Dutch government announced on March 26 that it would expel two Russian “intelligence agents” who worked at the Russian embassy in The Hague, without giving further details.

A spokesman for the Spiez laboratory declined to comment on the NDB statement, but said the government facility had previously been the target of cyber attacks.

In July the Spiez lab said hackers had circulated a malware-loaded document purporting to be a factsheet linked to a scientific workshop the lab organised, but that it was unaware of any direct attacks on the lab itself.

British authorities tested the Novichok found in Salisbury at Porton Down, a defence facility nearby, but have not said where else the substance might have been analysed.

The newspaper reports said the alleged Russian plot had gone beyond cyberattacks and that authorities found “equipment used for espionage” during their operation against the suspected spies.

In the weeks after the Skripal poisoning, Britain and dozens of other countries have kicked out scores of Russian diplomats, and Moscow has responded tit-for-tat in the biggest East-West wave of expulsions since the Cold War.