PESHAWAR: National Accountability Burau (NAB) summoned Pakistan Tehreek-e-Insaf (PTI) Chairman Imran Khan on Tuesday in a case pertaining to the misuse of Khyber Pakhtunkhwa (KPK) government’s helicopters. Khan is accused of allegedly using a Mi-17 and an Ecureuil helicopter of KP government for 74 hours which subsequently resulted in a Rs2.1 million loss to the national exchequer. On July 18, NAB had summoned Khan but citing his busy schedule, the PTI chief sought for some more time by submitting an application via his counsel Babar Awan. The scam was disclosed in January this year and in February the NAB chairman Justice (r) Javed Iqbal directed the bureau to launch a probe against the PTI chief and then-KP Chief Minister (CM) Pervez Khattak over the unofficial use of two government helicopters by misusing authority. Also read NAB summons Imran in helicopter misuse case Many government officials and Pervez Khattak have already appeared before the combined investigation team in the same inquiry.