President-elect Barack Obama and UN chief Ban ki-moon led the global community condemnation of the terror attacks in Mumbai and called on the nations of the world to work together to "root out and destroy terrorist networks".
At least 80 people, including Anti-Terrorism Squad chief Hemant Karkare, were killed when terrorists struck with impunity in Mumbai in coordinated multiple blasts and gunfire in a dozen areas across the city.
"These coordinated attacks on innocent civilians demonstrate the grave and urgent threat of terrorism," Obama's Chief National security Spokesperson Brooke Anderson said in a statement.
"The United States must continue to strengthen our partnerships with India and nations around the world to root out and destroy terrorist networks," he said.
"We stand with the people of India, whose democracy will prove far more resilient than the hateful ideology that led to these attacks," Anderson added.
In a statement, the US State Department condemned the terrorist attacks in Mumbai. "We are monitoring the situation very closely and stand ready to support the Indian authorities as they deal with this horrific series of attacks. At this point, we are unaware of any American casualties," it added.
The UN chief also strongly condemned the attacks, saying "such violence is totally unacceptable."
He said that no cause or grievance can justify indiscriminate attacks against civilians and called for the perpetrators of the attacks to be brought to justice.
British Prime Minister Gordon Brown said the "outrageous" attacks will be met with a "vigorous response". "I have sent a message to Prime Minister (Manmohan) Singh that the UK stands solidly with his government as they respond," Brown said, adding the UK is ready to offer all necessary help to India.
British Foreign Secretary David Miliband said the attacks were a reminder of the threat from violent extremists.
"Thursday's attacks in Mumbai which have claimed many innocent victims remind us, yet again, of the threat we face from violent extremists," he said.
"Our thoughts are with the families and friends of those killed and injured. The UK and India will continue their joint efforts to counter the actions of terrorists," he said.
The European Union strongly condemned the attacks and expressed its "horror and indignation" at the series of shootings and blasts.
Canada's Foreign Affairs Minister Lawrence Cannon condemned the attacks, saying "these cowardly attacks are truly appalling."
"Canada strongly condemns the savage terrorist attacks in Mumbai, which have left hundreds of innocent civilians injured or killed," Cannon said.
Britain's Liberal Democrat leader Nick Clegg said: "When violent terrorism raises its ugly head, it is crucial that the international community stands together.
Conservative leader David Cameron said his thoughts were with all those who had been caught up in the attacks.
"India and Britain stand together at this time in the face of terrorism," he said.
The British Foreign Office has also issued an emergency number for people with relatives in Mumbai: 0207 008 0000.