Khan joined the Department of Sculpture, University of Dhaka as a lecturer in August, 1970. Soon began the War of Liberation of the country in March 1971. He had to face interrogation by the Pakistan Armed Forces but was left unharmed. Two days after the army crackdown in Dhaka on 25 March, he went to the New Market area and saw many dead bodies lying unattended. The ghastly scenes and atrocities of the war made permanent impressions in his mind, resulting in his series of works on the theme titled "Remembrance ‘71". The victims and the martyrs of the war remained a recurring theme in his imagery in the first two decades following the emergence of Bangladesh in 1971. He worked with his teacher Abdur Razzaque, in the first-ever commissioned sculptural work on the liberation war theme 1972. The piece, titled "Jagroto Chowrongi (The Vigilant Crossroads)" is the figure of a lone freedom fighter, has become a symbol of the heroic War of Liberation in the country.