Saudi Arabia's future king has tightened his grip on power through an anti-corruption purge by arresting royals, ministers and investors including billionaire Alwaleed bin Talal who is one of the kingdom's most prominent businessmen.
Prince Alwaleed, a nephew of the king and owner of investment firm Kingdom Holding, invests in firms such as Citigroup and Twitter. He was among 11 princes, four ministers and tens of former ministers detained, two senior officials told Reuters.
The purge against the kingdom's political and business elite also targeted the head of the National Guard Prince Miteb bin Abdullah.
News of the purge came early on Sunday after King Salman decreed the creation of an anti-corruption committee chaired by Crown Prince Mohammed, his 32-year-old favourite son who has amassed power since rising from obscurity three years ago.
Analysts say the arrests were another pre-emptive measure by the crown prince to remove powerful figures as he exerts control over the world's leading oil exporter.
The round-up recalls the palace coup in June through which Mohammed bin Salman ousted his elder cousin, Mohammed bin Nayef, as heir to the throne and interior minister.
MbS, as he is known, was expected to follow at least by removing Prince Miteb from leadership of the National Guard, a pivotal power-base rooted in the kingdom's tribes.
Over the past year MbS has become the ultimate decision-maker for the kingdom's military, foreign, economic and social policies, causing resentment among the Al Saud dynasty, parts of which have been frustrated by his meteoric rise.
The royal decree said the arrests were in response to "exploitation by some of the weak souls who have put their own interests above the public interest, in order to, illicitly, accrue money".
The line between public funds and royal money is not always clear in Saudi Arabia, an absolute monarchy ruled by an Islamic system in which law is not systematically codified and no elected parliament exists.
Many ordinary Saudis praised the crackdown as long-awaited.