Russian President Vladimir Putin demanded an apology from the Netherlands on Tuesday after what Moscow says was an attack on a Russian diplomat in The Hague by armed men in camouflage over the weekend.
Russia has lodged a formal diplomatic protest over the incident, in which it said a minister-counsellor at its embassy in the Netherlands, Dmitry Borodin, was badly beaten in his home in front of his children by the unidentified assailants.
"We are awaiting an explanation, an apology and also punishment of those responsible," Putin said at a news conference after an Asia-Pacific summit in Indonesia, calling the incident a "very rude violation" of diplomatic rules.
"Depending on how the Dutch side conducts itself, we will react," Putin said.
A Dutch police spokeswoman in The Hague, Ellen van Zijl, confirmed there had been an incident involving a Russian diplomat, adding: "This man is fine. He is not in the hospital."
She declined to give further details. The Dutch Foreign Ministry had no immediate comment.
Dutch news agency ANP said police had visited the home of Borodin, who is number two at the embassy, after receiving a complaint from neighbours about his treatment of his children.
A spokeswoman for the Russian embassy in The Hague, Sofia Sarenkova, said she believed such a complaint was "one of the pretexts" for the incident.
Sarenkova said the men who visited Borodin's apartment were "wearing something like police uniforms" but that they did not identify themselves. She said they pushed Borodin to the ground and beat him with a baton before taking him to a police station.
In Moscow, the Russian Foreign Ministry summoned the Dutch ambassador on Tuesday to demand an "exhaustive explanation".
The incident adds to tensions between Russia and the Netherlands, which are already at odds over the prosecution on piracy charges of environmental activists involved in a protest against Arctic oil drilling.
Last Friday, the Netherlands launched legal proceedings against Russia over the detention of Greenpeace activists on a Dutch-registered ship after their protest at an oil rig off Russia's north coast. Two of the 30 people arrested are Dutch.
On a visit to the Netherlands in April, Putin faced protests from gay rights activists over what human rights organisations say is repression of homosexuals in Russia. Putin denied Russia discriminates against gays.