Armed robbers stole £200,000 and "sensitive diplomatic documents" from a Saudi prince after holding up his entourage as they drove through Paris, French police reported.
Officers said a gang of "between eight and ten" thieves, two in BMWs, hijacked the first of 10 vehicles in the convoy, kidnapping three occupants before letting them go.
The robbery took place as the prince was making his way from a plush hotel on the Champs Elysees to an airport in Le Bourget.
It was reported the gang were armed with Kalashnikov rifles but an official later confirmed they were carrying hand guns.
The Saudis' Mercedes and one of the thieves' BMWs were later found abandoned and burned out 25 miles away.
A source close to the investigation told French news agency AFP: "For the moment, we have no details about the nature of these documents. They could be sensitive documents but they could equally well be unimportant."
No suspects have yet been apprehended.