Parts of a human body fell from a plane flying over the Saudi Arabian city of Jeddah on Sunday.
Police say they could be the remains of someone trapped in the undercarriage bay.
Spokesman Nawaf bin Naser al-Bouq told AFP: "Police received a telephone call at 2:30 am from a witness reporting the fall of human remains at an intersection in Mushrefa neighbourhood".
Al-Bouq added that the remains "fell from a plane's landing gear".
According to RT, a photo claiming to be the body has appeared on social media.
The incident comes after a Saudi Arabia Airlines plane carrying 315 passengers made an emergency landing in the city of Medina on Sunday.
However, a General Authority of Civil Aviation spokesman said there was no connection between the emergency landing in Medina and the Jeddah incident.
In September 2012, a stowaway plunged to his death from a plane in a residential street in Mortlake, London.
Resident Anne Williams told the Daily Telegraph: "I heard a monstrous bang. I thought someone had been hit by a car. There were two fellows going to church and they said there's a dead body in the street."
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