The crash comes a day after reports of a purge of princes and ministers in Saudi Arabia. A missile was also fired at a Riyadh airport from Yemen.
Saudi authorities arrested royal family members, sitting cabinet ministers and former government officials in an extraordinary purge that reportedly included the arrest of Prince Alwaleed bin Talal, a billionaire investor who owns major stakes in such companies as Twitter and Citigroup.
Saudi officials and media outlets framed the detentions as stemming from an urgent new drive to root out graft in the kingdom.
But it also appeared part of an ongoing effort by the country's ambitious and brash crown prince, Mohammed bin Salman, to consolidate power by eliminating rivals or critics in the event that his father, King Salman, soon abdicates the throne.
Lebanon's Shia Hizbollah group today accused Saudi Arabia of forcing Lebanese Prime Minister Saad al-Hariri to quit and has called for calm in an effort to contain the political crisis unleashed by his resignation.
Sayyed Hassan Nasrallah, the leader of Iran-backed Hizbollah, said there should be no political escalation in response to Hariri's declaration, which was made from Saudi Arabia and came as a surprise even to his aides.
Hariri, in a televised speech, said there was a plot to kill him, and accused Hizbollah and its Iranian backers of sowing strife in the Arab world.
Aides to Hariri, whose family made their fortune in the Saudi construction industry, strongly denied he had been detained or had been forced to resign.
Sunni Muslim Saudi Arabia, a political ally of Hariri, is locked in a bitter tussle for power across the Middle East with Shia Iran and its allies, including Hizbollah.
Lebanese President Michel Aoun will not accept Hariri's resignation until he returns to Lebanon to explain his reasons, palace sources said, delaying for now the politically difficult consultations over his successor.
- Reuters, DPA, AAP