Technically it’s J. P. Dutta’s, LOC: Kargil which has a 4 hr 25 min runtime. The film is based on the Kargil war fought between India and Pakistan. The film covers India’s lauch of Operation Vijay.
J. P. Dutta is known for multistarrer films and this film has an ensemble cast mainly Sunjay Dutt, Ajay Devgun, Saif Ali Khan, Abhishek Bachchan, Suniel Shetty, Akshaye Khanna, Nagarjuna, Manoj Vajpayee, Ashutosh Rana, Sanjay Kapoor, Rani Mukherjee, Kareena Kapoor, Raveena Tandon, Namrata Shirodkar, Mahima Chaudhry, Esha Deol, Isha Koppikar, Preeti Jhangiani and Priya Gill.
Besides this, Tamas (period television film - duration: 4 hr 58 min) which was aired on Doordarshan as a mini-series was later released as a feature film. It was screened at Indian Film Festivals. It cannot be considered as it is a television film and did not have a typical film release.
Also, the first uncut version of Lagaan was of more than seven hours and the combined duration of Gangs of Wasseypur (Part 1 & 2) is 6 hours. Though a continuation it was not a continous screening. So, it’s LOC: Kargil if continous screening is considered or else Gangs of Wasseypur (combined).
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