Related: Moscow suicide bombing kills at least 10

    MOSCOW, Aug. 31 (Xinhuanet) -- An Islamist group Tuesday claimed responsibility for a suicide bombing outside a Moscow subway station and vowed more attacks, as the death toll of the blast rose to 10.

    A statement published on an Islamist web site said the Islambouli Brigades group carried out "this heroic operation in support of Chechen Muslims" and that the attack was a blow to Russian President Vladimir Putin.

    Putin has firmly refused to negotiate with Chechen separatists and insists that they must be wiped out.     

    ISLAMIST GROUP CLAIMS RESPONSIBILITY

    Russia was being targeted as "a prelude to a bloody war against those who have devoted themselves to killing Islam and Muslims ...in Chechnya and other Muslim countries of the region," the statement said.

    The same group last week claimed responsibility for two Russian airliners' crashes that killed all 90 people aboard, saying the attacks were done in support of "our Muslim brothers in Chechnya."

    It warned of more operations after Tuesday's blast and last week's attacks on the airplanes.

    Meanwhile, according to Russia's Federal Security Service (FSB),the death toll of Tuesday's explosion has reached 10. More than 50were injured.

    The explosion was carried out by a female suicide bomber, Moscow Mayor Yuri Luzhkov confirmed Tuesday at the scene of the blast, the Rizhskaya (Riga) subway station northeast of downtown Moscow.

    The suicide bomber set off a shrapnel-filled explosive device outside the busy subway station, tearing through a crowded area between the station and a shopping complex. It was so powerful that two cars parked nearby caught fire.

    The blast, which Luzhkov said had the force of up to one kg. ofTNT, came two days after the election of a new pro-Moscow president in Chechnya as well as on the eve of the first day of school for most Russian children and ahead of the capital's weekend City Day celebrations.

    Luzhkov told reporters that the woman was walking toward the subway entrance when she saw two police officers, turned around and blew herself up.     

    TOLL LIKELY TO RISE

    The mayor said the toll could still rise because 16 of the injured were in grave condition. Four children were among the injured.

    Broken glass of the windows lay scattered alongside the two scorched cars at the metro station.

    Dozens of law enforcement officers have cordoned off the site and the metro station has been temporarily closed to traffic. Policemen accompanied by sniff dogs were searching for evidence at the scene.

    Investigators are trying to identify the type of the bomb and the explosives it contained. Earlier reports said the bomb was loaded with bolts and metal pieces.

    Moscow has tightened security following the blast, including heavier police presence at key administrative facilities and public gathering places.

    The city has suffered a wave of suicide bombings blamed on Chechen rebels since the end of last year. A female suicide bomber blew herself up outside a hotel adjacent to Red Square last December, killing five other people. In February, 41 people were killed in a rush-hour explosion on the Moscow subway that officials said was a terrorist attack.

    UN, US CONDEMNATION

    Following Tuesday' deadly blast in Moscow, UN Secretary-General Kofi Annan strongly condemned terrorist attacks in Israel and Russia and the gruesome murder of 12 Nepalese civilians in Iraq.

    "The secretary-general strongly condemns all hostage-takings and killings of innocent civilians, which no cause can ever justify," said the statement from Annan's spokesman.

    The UN Security Council also condemned in a statement the suicide bombing and "all other acts of terrorism."

    Also on Tuesday, the United States denounced the downing of Russian airliners and the suicide bombing in Moscow as "horrible attacks."

    "The United States condemns in the strongest terms the recent terrorist attacks in Russia," White House spokesman Scott McClellan said in a statement.

    US State Department spokesman Richard Boucher said at a news briefing that Washington was "very concerned" about the bombings in Moscow.

    "We have always been willing to help the Russians or consult with them in these matters," he said. Enditem