The Netherlands is expelling two alleged Russian spies working as diplomats after "rolling up" a spy network that targeted hi-tech industries, Dutch security officials said on Thursday.
The Russian officers from the civilian SVR intelligence service built up a "substantial" network of sources that could have damaged Dutch national interests, the Dutch General Intelligence and Security Service (AIVD) said.
Moscow said it would retaliate to the "provocative" gesture, which further strains a relationship that has been frosty ever since the 2014 shooting down of flight MH17 put the Netherlands and Russia at loggerheads.
The AIVD said in statement that it had "recently rolled up a substantial espionage network" involving the two Russians, who were both accredited diplomats at the Russian embassy in The Hague.
One of the Russians targeted people working in the Dutch high-tech sector, particularly companies dealing with artificial intelligence, semiconductors and nanotechnology, for uses in both civil and military applications, it said.
"Some individuals were paid by the intelligence officer in exchange for information," the Dutch intelligence service said.
The second officer played a "supporting role," it said.
The Russian ambassador had been summoned to the Dutch foreign ministry, Dutch interior minister Karin Ollongren said.
The spy network "likely caused damage to the organizations where the sources are or were active and thus possibly also to the Dutch economy and national security," Ollongren said.
The announcement comes a day after the Netherlands-based European Medicines Agency was hit by a cyberattack targeting coronavirus vaccine data, but there was no indication the two incidents were linked.
Leonid Slutsky, chairman of the Russian lower house State Duma's international affairs committee, said Moscow would be "forced to take symmetrical actions."
"I am sure that an adequate response will follow in a timely manner," Slutsky was cited by the Interfax news agency as telling reporters.
Slutsky described the Netherlands' move as "yet another provocative gesture" and the spying accusations were "unfounded."
Relations between The Hague and Moscow have been tense since Malaysia Airlines flight MH17 from Amsterdam to Kuala Lumpur was shot down in July 2014 over a part of eastern Ukraine held by pro-Russian separatists.
The Netherlands has said Moscow has responsibility for the disaster, which killed 298 people, 196 of them Dutch. Three Russians and Ukrainian are on trial in absentia over the crash.
Separately in 2018 the Netherlands expelled four alleged Russian spies after an alleged bid to hack the Organization for the Prohibition of Chemical Weapons in The Hague, using equipment in the back of a car parked in a neighbouring hotel.