The catalyst seems to have been an incident in a Warsaw park on 31 July, when a gang of Polish youths attacked, beat, and robbed three sons of Russian diplomats and their Kazakh friend. Robbery is not uncommon in Warsaw, and the Russian consul dismissed suggestions that there might have been underlying nationalist or political motives.
President Putin, however, was not so sure. He called the incident a "crime" and held the Polish authorities to account. The Russian media joined in, blaming the attack on what they called anti-Russian propaganda in the Polish media.
Then the tables were turned. First, a technical worker at the Polish Embassy in Moscow was attacked and beaten up. Then, three days later, the embassy's second secretary was assaulted. Both were hospitalized. The incidents, in both cases, took place just outside the embassy gates.
"Considering the incident that occurred three days ago, in which a technical worker of the Polish diplomatic mission was severely beaten near the embassy, we are beginning to think that [the incidents involved] hooligans with a poorly directed but clearly shaped political agenda," said diplomat Witold Jurosz, who works at the Polish Embassy in Moscow.
It is a view that has since been strengthened by another vicious assault on the Moscow correspondent of a major Polish newspaper. According to Jurosz, embassy staff are now taking special measures to ensure their safety.
"Our ambassador, Stefan Meller, had to issue special behavior instructions for our embassy staff in order to make sure every possible measure is taken to guarantee their safety," Jurosz said.
Not much love is lost between the two Slavic countries. When Russian presidential adviser Gleb Pavlovskii visited Warsaw recently, a Polish paper quoted him as complaining to the foreign minister that Poles talk about Russians the way anti-Semites talk about Jews.
The bad feeling has been brewing for some time. Poles resent President Putin's refusal to offer a Russian apology for the deal prior to World War II between Stalin and Hitler that led to the division of Europe and the loss of much Polish land. And they are angered that the official Russian commission into the 1940 massacre of thousands of Polish officers by the Red Army in the Soviet Union concluded that it was an ordinary criminal act -- not a crime against humanity.
The resentment simmers on both sides. Russian political commentator Yulia Latynina said she believes Poland's increasingly active foreign-policy role, most notably in Ukraine last November, is infuriating Moscow.
"The president of Poland [Aleksander Kwasniewski] played a very big role in what happened in Ukraine, and President Putin feels personally insulted," Latynina said. "And despite the official version that everything that happened in Ukraine was done by the [U.S. Central Intelligence Agency], in the Kremlin they know that Poland played almost the key role from an international point of view. The Polish support was the first support that started the international recognition of the Orange Revolution."
Moscow worries too that now that Poland is a member of the European Union, Warsaw will seek to shift opinion in Brussels against Russia.
Mutual suspicion, it seems, gnaws on recent as well as ancient doubts.
The Polish police today announced that they have arrested and charged two men in connection with the mugging of the Russian children and their Kazakh friend. The investigation, it said, was making good progress. But is anyone listening?
Another Pole Attacked In Moscow
Polish Diplomat Beaten Up In Moscow
Eastern Europe: Russian-Polish Tensions Rise Over Attack On Russian Children In Warsaw