Jaish-e-Mohammed terrorist Shahid Latif, believed to be the mastermind of the 2016 attack on an Indian Air Force base in Pathankot, was gunned down on Wednesday by unidentified assailants in a mosque in Daska town of Pakistan's Sialkot district, officials said.

Latif, alias Bilal, a designated terrorist under the Unlawful Activities (Prevention) Act, is learnt to have been shot dead along with two of his associates by three gunmen. He had infiltrated into the Kashmir Valley in 1993 and was arrested a year later.

He was in Jammu jail with Masood Azhar, founder of the JeM, till 2010, officials said.

He was deported to Pakistan in 2010 following his release and formally joined the terror group, they said. "This is the biggest blow to JeM on Pakistan soil," an official said. Latif was wanted by the National Investigation Agency (NIA).

Seven IAF personnel were killed when four JeM terrorists sneaked into the Pathankot Air Force Station on January 2, 2016. The siege went on for three days.