Islamabad (PTI): In a blunt message to Pakistan, the USon Thursday asked it to investigate the "circumstances" under which Mumbai terror attacks were carried out and take the responsibility of dealing with non-state actors operating from its territory.

US Secretary of State Condoleezza Rice, who flew in on Thursdaymorning from New Delhi and held talks with President Asif Ali Zardari and Prime Minister Yousuf Raza Gilani, said Pakistan must provide "robust" and "effective" cooperation to India in bringing the perpetrators of the Mumbai terror strikes to justice.

"We talked at length about the importance of Pakistan taking its responsibility to deal with those who may use Pakistan territory even if they are non-state actors," she said at a press conference here after her meetings with the Pakistani leadership.

"Pakistan needs to investigate the circumstances under which these attacks took place in Mumbai," said Rice who was provided evidence by India yesterday about involvement of Pakistan-based terrorists in last week's attacks.

"There is a lot of information. There are many mechanisms for sharing information and mechanisms should be used," she bluntly told Pakistan.

Noting that the sophistication seen in the Mumbai strikes was never witnessed earlier in this part of region, Rice said "there is urgency to get to the bottom of these attacks, urgency to bring perpetrators to justice and urgency to use this information to disrupt and prevent further attacks."