Police in Pakistan have arrested a Shia Muslim leader in connection with the assassination of a rival Sunni lawmaker last month, amid a crackdown on several Islamic groups.
By Paul Anderson
BBC correspondent in Islamabad
Interior Ministry officials say they arrested Allama Sajid Naqvi in connection with the murder of Maulana Azam Tariq, a leader of an extremist group from Pakistan's Sunni majority.
Tariq's death sparked anti-Shia riots
They did not say how he might have been involved.
Mr Nakvi leads the Shia militant group Tehreek-i-Islami Pakistan, which is one of several organisations banned by President Musharraf on Saturday.
Most of the groups, Sunni and Shia, had already been banned in security sweeps ordered by the president in the past two years, but they had simply renamed themselves and continued operations as before.
Those include militant attacks in Kashmir and the killing of Westerners and foreign and Pakistani Christians last year.
Rash of attacks
There has also been a spate of sectarian attacks, the worst of them when more than 50 Shia worshippers were gunned down in a mosque in July.
President Musharraf has signalled now he is taking a much tougher line, partly as a result of pressure from the United States.
The authorities closed the offices of a number of banned groups in cities across the country and have moved to expel thousands of foreigners from Pakistan's religious schools, or madrasas.
Many of these are seen as nurseries for Islamic extremism.