Pakistan has arrested more than 100 people in a crackdown on groups allegedly linked to the Mumbai attacks, but that information India has handed over still needs work before it can be used as evidence in court, a top official said Thursday. Despite the announcement, Interior Ministry chief Rehman Malik dodged a question on whether Pakistan was conceding the plot that killed 164 people in India's commercial capital was hatched on his country's soil. India says a Pakistan-based militant group, Lashkar-e-Taiba, masterminded the November attack. In the days afterward, the UN Security Council declared that Jamaat-ud-Dawa, a charity in Pakistan, was merely a front for the outlawed militant organization. In a press conference, Malik said 124 people had been arrested, while authorities had taken steps against 20 offices, 87 schools, two libraries, seven religious schools, and a handful of other organizations and Web sites linked to the charity. He also said authorities had shut several relief camps of the charity, some of which have been alleged to be militant training grounds. It was unclear exactly how many people remained in Pakistani custody, however, and Malik at one point indicated many may simply be under surveillance now. Among those who are being held, including under house arrest, are Hafiz Mohammed Saeed, the head of the charity who helped establish the militant group, which was banned in 2002. Also in custody are Zaki-ur-Rehman Lakhvi and Zarrar Shah, two men India alleges planned the Mumbai attacks.