US President Barack Obama called his Russian counterpart Dmitry Medvedev to expresses his condolences on the deadly bombings in Moscow and offered US cooperation to bring the perpetrators of the blasts to justice. A White House official said, Obama telephoned Medvedev yesterday, and personally conveyed the condolences of the American people on the loss of life and injuries resulting from the outrageous terrorist act. President Obama said that the United States is ready to cooperate with Russia to help bring to justice those who undertook the attack. The US Secretary of State Hillary Clinton said terrorist activities and networks across the world had links to each other. Ms. Clinton said, in an interview to the Canadian TV that, there is a connection among most of the terrorist activities around the world who encourage each other and also exchange training, explosives, and information. India also joined the world community in condemning the dastardly act. Describing the twin blasts in Moscow as most horrific act of violence, the Prime Minister Dr Manmohan Singh in a letter to President Medvedev expressed India's solidarity with Russia. UN chief Ban Ki-moon strongly condemned the suicide bomb attacks and said that the Russian authorities will bring to justice the perpetrators of this heinous terrorist attack. French President Nicolas Sarkozy said the Moscow metro bombs are not different from the 9/11 attacks on the United States, and that Russia deserves the support of all democracies. Russian President Dmitry Medvedev and Prime Minister Vladimir Putin vowed to eliminate the perpetrators of the twin blasts. The Russian Foreign Minister, Sergei Lavrov said, suicide bombings in Moscow show the need for an even stronger international cooperation to prevent future attacks. Speaking at the G-8 meeting in Canada, Mr. Lavrov urged world leaders to fight what he called the global terrorist network. Meanwhile, Moscow is holding a day of official mourning for the thirty eight people killed in yesterday's twin suicide bombings on the city's Metro. Officials blamed the attacks on Muslim groups from the northern Caucasus, where rebels have been waging violent campaigns for independence.