An international flight was delayed nearly seven hours after a passenger opened a plane's emergency exit door after mistaking it for the bathroom, according to reports.

A traveler Friday on a Pakistan International Airlines flight from Manchester, London, to Islamabad, Pakistan, opened the exit before takeoff, which automatically deployed the emergency slide, CNN and The Independent report.

"We regret the delay of PK771, which is an unfortunate consequence of the delay of PK702, caused due to a passenger opening the emergency door," the airline later tweeted. "We strongly urge passengers to follow security instructions as such mishaps result in inconvenience of hundreds of other passengers."

Passengers were off-loaded and eventually brought back onto the flight. One traveler voiced frustrations on social media, claiming the airline lost their luggage and criticized PIA for "pathetic service."

"Nobody at airport telling us what happened to our luggage," user @WaterLileee wrote. "After 3.5 hours of frantic searching we get to know it wasn't even brought in the first place."

USA TODAY has reached out to Pakistan International Airlines for comment.

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