A flight from Frankfurt to Hanoi was diverted to Calcutta early on Wednesday after a passenger was taken ill mid-air, airport officials said.
Ludwig Manfred Buhler, 66, a German national, underwent surgery at a private hospital in Calcutta.
Hospital officials said he had suffered a cerebral haemorrhage and was on ventilation support on Wednesday evening.
Buhler was on a Vietnam Airlines flight when he fell ill, said Calcutta airport officials.
“The flight was diverted to Calcutta because of a medical emergency. It landed at the Calcutta airport at 3.32am,” said an airport official.
The plane to the capital city of Vietnam had 276 passengers.
According to airport sources, when the doctor examined Buhler early on Wednesday morning, he was unconscious.
Buhler was shifted to Apollo Multispeciality Hospital on EM Bypass from the airport.
“The patient suffered a stroke leading to cerebral haemorrhage. He underwent surgery and has been put on ventilation support,” said an official of the Apollo hospital.
“His condition is very critical,” the hospital official added.
The airport authorities and the hospital have informed the German consulate in Calcutta about Buhler.
The flight finally took off for Hanoi on Wednesday morning after routine
procedures, said airport officials.