A flight from Manchester was delayed for almost eight hours when a confused passenger opened an emergency exit after mistaking it for the toilet door.

The Pakistan International Airways (PIA) flight to Islamabad was nearly ready to depart when the woman grasped for the wrong door, launching the emergency evacuation slide.

The startled passenger told airline staff she thought the door was for the toilet. The airline and Manchester airport confirmed the details of the incident.

Officials in Pakistan blamed a shortage of airline staff for allowing the emergency exit door to be opened, according to the English-language newspaper Express Tribune.

The flight carrying nearly 400 passengers eventually left Manchester at 5am on Saturday. It arrived in Islamabad seven hours late having made up some time during the journey. Several other departures from Manchester were also delayed as a result of the disruption.

The travel misery did not end there. Flight PK702 was only able to take off when 38 passengers volunteered to disembark, owing to its evacuation capacity being reduced, and some of those have since complained that their baggage was left behind in Manchester.

One passenger, tweeting as Sleeping Beauty, wrote after arriving in Islamabad on another flight: “Pathetic service from pia. I am one of the 38 passengers who voluntarily off loaded from PK702 so it can fly to islamabad only on the condition that all 38 of us will get our luggage … Then when we reached here today we were told half of our luggage is still at Manchester airport. We have suffered a lot.”

A PIA spokesman said: “All passengers were provided dinner. The offloaded passengers were provided with transportation and hotel accommodation and will be adjusted on the next available flight. PIA regrets the inconvenience caused to its passengers due to this incident.”