The militant Islamic groups banned in Pakistan include several groups which have been often blamed for a stream of sectarian violence in the country.
The Islamic Sunni Sipah-e-Sahaba and the Shia Tehrik-e-Jafria have been accused of attacking followers of the rival sects.
Tariq took charge of Sipah-e-Sahaba after the death of Jhangvi
The Lashkar-e-Jhangvi is another Sunni group accused of violence.
President Pervez Musharraf says about 400 people were killed in the country in sectarian violence last year.
Sipah-e-Sahaba - or the Army of Prophet Mohammad's companions - is a radical group from the majority Sunni sect of Islam.
The group was founded by a Sunni cleric - Maulana Haq Nawaz Jhangvi - in the early 1980s to block the influence of the Iranian Shia revolution in Pakistan.
The next two decades saw an explosion of sectarian violence between Shia and Sunni extremist groups and the death of hundreds of people.
Sipah-e-Sahaba wants Pakistan to be officially declared a Sunni Muslim state.
It has strongholds in southern districts of the populous central province of Punjab and the volatile port city of Karachi.
Maulana Jhangvi was assassinated in a suspected sectarian attack in 1990.
The killing led to the formation of a breakaway and more radical Jhangvi group which was banned last year.
Maulana Azam Tariq, who was assassinated on 6 October 2003, then took charge.
Maulana Tariq had been detained by the authorities a year earlier at the height of violent protests by hardline Islamic groups in support of Afghanistan's Taleban regime.
Tehrik-e-Jafria - or the Movement of Followers of Shia - was founded in 1979.
Its creation coincided with the enforcement of controversial Islamic laws by the then military ruler of Pakistan, General Mohammad Zia-ul-Haq.
Most of the victims have been Shias
The Islamic revolution in predominantly Shia Iran around the same time gave an added boost to the organisation.
Its leader, Allama Arif Hussain al-Hussaini, was a student of the leader of Iran's Islamic Revolution, Ayatollah Khomeini.
The Lashkar-e-Jhangvi was formed in 1996 by a faction that broke away from the Sipah-e-Sahaba after the assassination of Maulana Jhangvi.
They accused the parent group of deviating from his ideals.
Said to be even more radical than the Sipah-e-Sahaba, they were banned in 2002 and designated as a terrorist group by the US State Department in January 2003.
The Lashkar-e-Jhangvi said it carried out one of the worst sectarian attacks in recent years, when more than 50 people were gunned down in Quetta in July 2003 when they were praying in front of a Shia mosque.
The US believes it has close ties with Osama Bin Laden's al-Qaeda network.
They are also blamed for involvement in the murder of US journalist Daniel Pearl in Karachi in 2002.
Another group banned is the Tanzeem-e-Nifaz-e-Shariat-e-Mohammadi.
This radical Sunni Muslim group was founded by Maulana Sufi Mohammad.
He was a follower of Saudi Arabia's Wahhabi school of thought.
The group has been engaged in violent agitation for the enforcement of Islamic laws in its stronghold of Malakhand in north-western Pakistan.
In the late 1980s, then Prime Minister Benazir Bhutto ordered paramilitary forces to crush a revolt by the group.
In October last year, Sufi Mohammad crossed into Afghanistan with thousands of his followers to help the Taleban fight US-led forces.
But he returned soon after the collapse of the Taleban.
He has since been under detention.