Pakistan said on Thursday it would help India to bring those behind the Mumbai terrorist attacks to justice, saying it had shut down extremist Web sites and suspected militant training camps, and detained 71 people in a deepening probe. Still, a top Pakistani official said authorities needed to further investigate information about the attacks provided by arch-rival India before it could be used to prosecute suspects in court. Islamabad is under pressure to clamp down on Lashkar-e-Taiba, the Pakistan-based militant group that India blames for killing 164 people in its commercial capital in the siege and raising tension between South Asia's nuclear-armed neighbors. Days after the November attacks, the UN Security Council declared that Jamaat-ud-Dawa, a charity in Pakistan, was a front for the outlawed militant organization. On Thursday, Pakistan's Interior Ministry said 71 leaders of the groups had been arrested since then and that another 124 had been placed under surveillance and must register their every move with police. “The restrictions are so tough. It's virtual detention,” Interior Secretary Kamal Shah said. Rehman Malik, the ministry's top official, said authorities also had closed 20 offices, 94 schools, two libraries and six Web sites linked to the charity. He said authorities had shut more than a dozen relief camps of the charity, some of which are alleged to be militant training grounds. Among those detained was Hafiz Mohammed Saeed, the head of Jamaat-ud-Dawa, along with Zaki-ur-Rehman Lakhvi and Zarrar Shah, who India says planned the Mumbai attacks. Malik repeated Islamabad's call for a joint probe into the attacks and urged India to hand over more information to assist Pakistan's own probe. “We are fully committed to help India in this investigation,” he said. “We have to prove to the world that India and Pakistan stand together against the terrorists because they are the common enemies.” On Jan. 5, India handed Pa-kistan a dossier of evidence including information on interrogations, weapons and data gleaned from satellite phones used by the attackers.