At least 15 kilogrammes of heroin were recovered from a Pakistan International Airlines (PIA) flight on Tuesday at the Jinnah International Airport in Karachi, the national flag carrier reported on Tuesday.

"PIA's security department, with the assistance of Anti-Narcotics Force, has recovered approximately 15 kg of heroin from an aircraft which was at the hangar in Karachi undergoing [a] C check," the PIA spokesperson, Daniyal Gilani, said in a statement.

C checks are conducted in a hanger at a maintenance base after a specific amount of actual flight hours, and require that a large majority of the aircraft's components be inspected.

"The matter is being investigated by all agencies concerned," the statement added.

Several attempts have been made to smuggle illegal drugs on PIA flights in the past.

In May 2016, 27kg of heroine was recovered on board a PIA aircraft while routine maintenance was being carried out at a PIA hangar at the Karachi airport.

PIA crew members have also been arrested in the past for attempting to smuggle narcotics on flights bound for international destinations.