Security is always tight in Kashmir, due to the very real threat of terrorist violence. (Which is, after all, what this film is about.) But when lead actor Hrithik Roshan arrived on location to start shooting Mission Kashmir, his first film had not yet released to theatres, so no one recognized his face. Arriving for the first day's shoot dressed as a Kashmiri militant, which he portrays in the film, security thought Hrithik really WAS Kashmiri - because of his fair skin and light colouring - and refused to allow him on set! Shortly thereafter, on 14 Jan 2000 Hrithik's début film Kaho Naa Pyaar Hai turned him superstar overnight, 'Hrithikmania' swept India ... and his face was instantly recognized everywhere.
The only film in which Jackie played a villain while Sanjay Dutt an honest cop, in their other films like Khalnayak,Kartoos and Jung Jackie played an honest cop.
Rakesh Roshan openly stated he did not like the film due to a major hole in the script. There was no explanation given or shown as to where Hrithik's character was from childhood to adulthood ( 8 years).
Shah Rukh Khan and Amitabh Bachchan were both offered the main roles of Altaf and Inayat, but couldn't fulfill it due to their commitment to Mohabbatein (2000) which released the same Diwali weekend.
Mission Kashmir's promos and trailers were made by Rajkumar Hirani who is now a respected director in his own right.