Pakistan on Thursday put under house arrest Hafiz Saeed, the founder of Lashkar-e-Taiba, an Islamist militant group blamed for the attacks on Mumbai.
India's prime minister demanded the total elimination of the "epicentre of terrorism" in Pakistan.
The Pakistan-based militant group has denied being behind the Mumbai attacks, which killed at least 179 people, and said it condemned them.
Here are some details about the group:
Who are lashkar-e-taiba?
-- Lashkar-e-Taiba - "The army of the pure" - was a militant offshoot of Markaz Dawatul Irshad, an Islamic charity and educational organisation. Markaz Dawatul Irshad has since been renamed Jamaat-ud-Dawa, which was at the forefront of relief work after a 2005 earthquake killed 73,000 people in Pakistani Kashmir and the North West Frontier Province.
-- Pakistan-based Lashkar made its name fighting Indian rule in Kashmir.
-- It was founded in 1989 by Hafiz Mohammad Saeed and Zafar Iqbal. Saeed was a former teacher of Islamic studies at Lahore's University of Engineering and Technology.
-- Lashkar based its philosophy on Wahhabism, the austere brand of Islam practised in Saudi Arabia, and has relied on donations from overseas.
-- The group's objective is to Islamicise South Asia and to end Indian rule of Muslims in Kashmir.
What have they done?
-- The militant group claimed responsibility for the attack on an army base in New Delhi's historic Red Fort which killed three people in late 2000. It also claimed responsibility for an attack on Srinagar airport in Jan. 2001 that led to the deaths of five Indians and six militants and an attack in April 2001 on Indian border security forces.
-- In Dec. 2001 gunmen raided India's parliament, killing 14 people. India accused the Pakistan-based Jaish-e-Mohammad and Lashkar-e-Taiba groups of being responsible, and the incident nearly brought nuclear-armed India and Pakistan to the brink of a fourth war. Lashkar denied it was involved.
-- The group was blamed for bomb attacks on markets in New Delhi that killed more than 66 people in Oct. 2005. Lashkar denied it.
-- Former Pakistani President Pervez Musharraf banned the two groups accused of the attack on India's parliament in Jan. 2002. Lashkar was banned in India in 2001 and designated a "foreign terrorist organisation" by the United States.
-- The United States froze the assets of four prominent members of Lashkar in May 2008. The four included Saeed, described by the Treasury as Lashkar's chief, playing a major role in its operational and fund-raising activities.
-- It named the others as Pakistan-born Zaki-ur-Rehman Lakhvi, chief of operations, Haji Muhammad Ashraf, chief of finance and India-born Mahmoud Mohammad Ahmed Bahaziq, described as the main Lashkar financier in the 1980s and 1990s.
-- A U.N. Security Council committee on Wednesday added Saeed and his charity Jamaat-ud-Dawa to a list of people and organisations linked to al Qaeda or the Taliban.