Washington (PTI): Dissatisfied over the steps taken by Pakistan to bring the perpetrators of the Mumbai terror strikes to justice, a US senator said Islamabad needs to do much more and quickly against those responsible for the attacks.

"It is absolutely imperative that Lashkar's leaders are not just detained by Pakistani authorities, but that they are prosecuted for the terrorist acts that occurred," Senator Joseph I Lieberman, the Chairman of the Senate Committee on Homeland Security and Government Affairs, said on Thursday.

He was in New Delhi a few days after the Mumbai terror attacks and met top Indian leaders including the Prime Minister Manmohan Singh.

Top American intelligence and police officials were asked by the powerful Congressional Committee on Wednesday to testify before it on the lessons US has learnt from the ghastly Mumbai terror attack.

Under Secretary for Intelligence and Analysis and Chief Intelligence Officer Charles E Allen, Chief Intelligence Officer, Directorate of Intelligence, National Security Branch, Federal Bureau of Investigation Donald Van Duyn and the New York City Police Commissioner Raymond W Kelly were asked to testify before the committee.

In her opening remarks, Ranking Member of the Committee, Senator Susan M Collins said the implications of the terrorist group, Lashkar-e-Taiba, has links that reach far beyond South Asia.

"By examining the command, control, and coordination of the government response; the adequacy of equipment and training and public-information arrangements in place during the Mumbai attack, we can improve our efforts to prevent similar attacks," Collins said.