Islamabad: With India insisting that terrorists involved in the Mumbai attacks had Pakistani links, the United States today asked Islamabad to "investigate aggressively" whether any groups based in the country had any possible connections to the last week's deadly strikes.

Visiting Admiral Mike Mullen, chairman of the US Joint Chiefs of Staff, met President Asif Ali Zardari and held discussions with him about the Mumbai terror attacks that claimed over 180 lives.

"In his talks with Pakistani leaders, Mullen urged them to investigate aggressively any and all possible ties to groups based in Pakistan," the US embassy said in a statement.

It said the Pakistani leadership also conveyed its commitment to jointly work with India to investigate the Mumbai attacks.

"All agreed that the tragedy in Mumbai represents a dangerous escalation in the sophistication of extremist attacks and an increased threat to the entire region," the statement said.

Mullen's comments came soon after US Secretary of State Condoleezza Rice said in New Delhi that Pakistan should "cooperate fully and transparently" with India's investigation into the terror strikes.

Source : IANS