German police said on Friday that the man’s body was found in the wheelhouse of a Lufthansa plane en route from Iran to Frankfurt Airport.
A spokesman for the regional police in Hesse, western Germany, said the body was found during renovations.
The plane from Tehran landed on Thursday morning in Frankfurt.
The police added that they found an oxygen cylinder with a mask next to the body, explaining that they currently do not have additional information about the identity of the man and the circumstances of the tragedy, and indicated that they had launched an investigation.
It comes at a time when Iran is witnessing a wave of large-scale demonstrations that are being brutally suppressed, resulting in dozens of deaths and arrests of hundreds of protesters to date.
Protests erupted following the death of 22-year-old Mahsa Amini on September 16, three days after she was arrested in Tehran on charges of violating Iran’s strict women’s dress code.