The controlled airspace of Bir Tikendrajit International Airport in Manipur's capital Imphal was closed for commercial flight operations today for nearly three hours after an unidentified flying object was seen. Here are the details of what happened, according to sources in the Airports Authority of India (AAI). At 2.30 pm, the Imphal air traffic control (ATC) got a call from the Central Industrial Security Force (CISF) control room that an unidentified flying object was seen just above the ATC tower.