The United States has clamped down on Pakistan-based terrorist organisation Laskar-e-Toiba, which has repeatedly targeted India, by freezing the assets of its top four leaders and barring its nationals from dealing with the terrorist outfit.

The four are Muhammad Saeed, the group's overall leader, Zaki-ur-Rehman Lakhvi, its chief of operations; Haji Muhammad Ashraf, the chief of finance--- all hailing from Pakistan-- and India-born Mahmoud Mohammad Ahmed Bahaziq, a LeT financier, the US Treasury Department said. It said Lashkar had links to terror mastermind Osama bin Laden and the al Qaeda network.

"LeT is a dangerous al Qaeda affiliate... its transnational nature makes it crucial for governments worldwide to do all they can to stifle LET's fundraising and operation," said Stuart Levey, Under Secretary for Terrorism and Financial Intelligence.

The LeT has masterminded and carried out numerous attacks against Indian military and civilian targets since 1993, including the December 2001 attack on Parliament and the July 2006 attack on Mumbai's local trains.

The LET is also suspected of involvement in attacks in New Delhi in October 2005, and in Bangalore in December 2005. LeT arose in the early 1990s as the armed wing of the Sunni missionary movement Markaz-ud Dawa-wal-Irshad. Despite being banned by the government of Pakistan in January 2002, LeT continues to operate in Kashmir and engage in or support terrorist activities worldwide, the US statement said.

The US had named LET a Foreign Terrorist Organisation on December 26, 2001. "Any assets these designees have under US jurisdiction will be frozen and US citizens are prohibited from engaging in any transactions with the designees," it said.