KATHMANDU: The Commission for Investigation of Abuse of Authority (CIAA) summoned Nepal Oil Corporation (NOC) Managing Director Gopal Prasad Khadka on Tuesday for interrogation on the under-investigation land-purchase irregularity case. Spokesperson for CIAA Padam Prasad Pandey said that this was a regular interrogation conducted on the under-investigation case. 'Many people related to the case are being questioned and NOC Chief has been summoned along with all concerned parties, as a part of routine investigation,' said Pandey. A cabinet decision in September last year had removed Khadka from his post on charge of committing irregularities while purchasing land plots for the corporation in various areas. Later, the Supreme Court issued an interim order in his favour, against the government decision.