The LeT was responsible for the Mumbai terror attacks in 2008 that killed 166 people. (Representational)

At least 300 fighters from Pakistan-based Lashkar-e-Taiba (LeT), designated a global terror organisation by the US and the UN, are active in war-torn Afghanistan, a pentagon report has said.

The report also identified LeT among the three terrorist groups posing the greatest threat to the US and its allied forces in Afghanistan.

The LeT was responsible for the Mumbai terror attacks in 2008 that killed 166 people.

Among the 20 prominent terrorist organisations active in Afghanistan, LeT ranks fifth in terms of fighters along with al Qaeda and Islamic Movement of Uzbekistan, stated the Pentagon report, ''Lead Inspector General for Operation Freedom''s Sentinel'', for the quarter ending March 31.

The report said the Department of Defence "identified the Haqqani Network, the Eastern Turkistan Islamic Movement (ETIM) and Lashkar-e-Taiba as groups that present the greatest threat to US and allied forces in Afghanistan".

The report also stated that an estimated 300 LeT and 1,000 Islamic Emirate High Council operatives are active in the war-torn country.

The ISIS-K, Tehrik-e-Taliban Pakistan and Haqqani network with an estimated 3,000-5,000 fighters each top the list of terrorist groups active in Afghanistan, it said.