He wanted to take a large shipment of illicit drugs on board of the aircraft.

On Monday, October 26, at the international airport of Beirut Rafic Hariri the prince of Saudi Prince Waleed Bin Abdul Mohsen Bin Abdul Aziz was detained: he was suspected of drug smuggling.
A member of the royal family was handcuffed when he was going to fly from Lebanon to Saudi Arabia on a private jet, according to TV channel Al-Mayadeen. During the inspection border guards discovered that he had a cargo of drugs with him. According to law enforcement, 40 packages of drugs with a total weight of two tons were confiscated. Meanwhile, the name of the narcotic substance was not specified.

By the way, 25 September a 28-year-old Saudi Prince Majid Abdul Aziz Al Saud was arrested in Los Angeles. He was accused of attempted rape: according to the police, he wanted to force women working in his rented house in the Beverly Hills to perform oral sex.