MOSCOW, Aug. 11 (Xinhuanet) -- The Russian Foreign Ministry on Thursday expressed deep regret over Wednesday's attack against a Polish diplomat, the Interfax news agency reported. Russian Deputy Foreign Minister Sergei Kislyak met Polish Ambassador Stefan Meller and expressed regret over the incident. "Deep regret was expressed on behalf of the Russian Foreign Ministry leadership over the ruffian attack on Second Secretary ofthe Polish Embassy Marek Reszuta on Aug. 10," the Russian Foreign Ministry said in a statement on Thursday.

    "It was emphasized that the incident involving the Polish diplomat is being carefully investigated by Russian law enforcement agencies, which are doing all they can to find those responsible," said the statement.

    The Russian side has taken additional measures to protect the security of the Polish embassy in Moscow and its staff, it said. The Foreign Ministry also expressed hope in the statement that "the incident will not be used to fan tensions in the Russian-Polish relations."

    A Polish diplomat was beaten in Moscow on Wednesday, the second attack against Polish diplomats in four days, prompting an outcry from Warsaw for punishment against the attackers and heightened security to protect its diplomats.

    The attacks on Polish diplomats happened days after unidentified Polish attackers beat up three sons of Russian diplomats in Warsaw and grabbed their mobile phones and properties. Russia demanded an apology from Poland. The Polish Foreign Ministry expressed regret over the assault but stopped short of an apology, saying the attack was not politically motivated. Enditem