A Ryanair flight en route to Manchester Airport from Albania's Tirana made an emergency landing at London Stansted on Sunday after a passenger died onboard, media reports said.

After crossing Switzerland and France, the flight was diverted shortly before 8 pm on Sunday, according to Metro.

Upon landing, the aircraft was attended by emergency crews, including paramedics, police, and an air ambulance.

Despite their efforts, the man, whose age and identity have not been disclosed, was declared dead on arrival.

The incident caused chaos among passengers as they tried to cope with the unexpected situation.

According to an eyewitness, the man began "having convulsions" when crew members rushed to him.

They even moved him to the aisle where CPR was administered in a desperate bid to save his life.

"He stopped breathing and everything went into chaos. A few of us with first aid training jumped in to help and started CPR while the defibrillator was set. Two aircrew members and three passengers managed to keep doing CPR as instructed by the defibrillator for 25 minutes when we finally landed in an emergency in London," the eyewitness told the Manchester Evening News.

"The paramedics continued for another 30 minutes when we were all instructed to leave the plane. After about another hour, the ambulance was still there but we boarded again with a new aircrew to continue the trip to Manchester, without the man and his friends. I asked and was told that, unfortunately, the man did not make it. I was devastated to learn the sad news," he added.

A spokesperson for the East of England Ambulance Service said: "One ambulance, one Hazardous Area Response Team vehicle, one paramedic car and Essex and Herts Air Ambulance were called to Stansted Airport on Sunday evening following reports of a man with a medical emergency on an aircraft. Sadly, despite the best efforts of all involved, the man had died at the scene."