The Dawn said that while the Pakistani customs had launched a probe, the drugs could not have been concealed in the panels and other recesses of the plane without the involvement of other airport personnel.
"Clearly, the investigation needs to be on a broader level," an editorial in the daily said.
"PIA has suffered enormously at the hands of the powerful rackets that operate within it, and it needs to be rescued from their clutches if it is to survive."
The editorial came as crew members of a PIA flight in which heroin was found after it landed in London returned to Islamabad.
The crew made its way back from Heathrow Airport, where their passports were seized by British authorities who searched the plane and questioned them after landing on Monday.
British authorities confirmed on Wednesday that Border Force officers had found a "quantity of heroin" on board the PIA flight.
PIA spokesperson Mashhood Tajwar said British authorities had "thoroughly searched" and detained the flight crew after they landed at Heathrow, the Dawn reported.
The Pakistan carrier has come under fire for poor performance, low safety standards and the staff's unprofessional attitude.
Members of PIA crew have been sacked for smuggling contraband and assisting money laundering operations.
The Dawn said: "The national flag carrier has suffered another blow to its image.
"It is almost impossible that the contraband could have been placed in the plane without the involvement of some members of the ground handling staff or maintenance personnel."
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)