Maintaining that the Mumbai [Images] attackers had links that lead to Pakistani soil, the United States has asked Islamabad [Images] to pursue leads provided by New Delhi [Images] and track down the perpetrators of the deadly terror strikes.

It was clear that the attackers had links that lead to Pakistani soil, visiting Assistant Secretary of State Richard Boucher said on Monday.

Boucher, whose arrival in Islamabad coincided with India handing over evidence about the terrorist attacks to Pakistan, said the US wants Islamabad to investigate the information provided by New Delhi, follow available leads and track down perpetrators so that similar attacks do not occur in future.

India and Pakistan both had pieces of the puzzle and need to cooperate, Boucher told the news conference at the US embassy after talks with the country's top leadership.

"The two sides need to exchange information," he said, adding that India and Pakistan need to work together as this alone will ensure that the perpetrators of the attacks are tracked down.

The US had a direct interest in the probe as six of its citizens were killed in the Mumbai attacks, he said, adding, "We are interested that those responsible must be found."

Asked whether the US believed Pakistan's state institutions, including the ISI, was linked to the strikes, Boucher said: "Let us find out from the evidence (handed over by India) who was involved in these attacks and not jump to conclusions."