The Crown Prince of Saudi Arabia is expanding his power over the Middle East country with a reported anti-corruption campaign.
King Salman named his son Mohammed bin Salman Crown Prince in June. The 32-year-old prince replaced his cousin Mohammed bin Nayef as the next in line to be King.
There have been no public displays of opposition to the campaign within the kingdom.
But outside observers say the prince is removing opponents to expand his own power. In the Washington Post newspaper, Saudi reporter Jamal Kashoggi wrote that the Saudi royals usually share power and rule by consent.
He added, "Crown Prince Muhammad bin Salman is upending this arrangement and centralizing all power within his position as crown prince."
Almost 50 people were detained early Sunday, including 11 princes, four government ministers and one billionaire.
A royal order on Saturday said the campaign was launched in reaction to abuses of power. The order said some officials had put their own interests above the public interest, in order to make money illegally.
A Saudi official told Reuters that the men are accused of several serious financial crimes, including bribery. The accusations could not be confirmed independently. Family members of those detained could not be reached.
The detainees are being held in hotels in the capital. And a no-fly list has been created to prevent owners of private airplanes from leaving the country.
Prince Mutaib bin Abdullah is among those detained. He has been serving as head of Saudi Arabia's National Guard. He was responsible for security in the capital and the guarding of members of the royal families.
The moves give Crown Prince Mohammed bin Salman control of all Saudi security and military forces. That power has long been divided among branches of the royal family.
Prince Alwaleed bin Talal, a billionaire with holdings across the world, is also among those arrested. His holdings include shares of News Corp, Citigroup and Twitter and ownership of hotel companies.
Former Economy Minister Adel Faqieh was also arrested along with some leading Saudi businessmen. Some experts questioned the decision as these are men the kingdom was depending on for help in moving the country from an oil-based economy.
Greg Gause is a Middle East expert at Texas A&M University. He told Reuters, "It seems to run so counter to the long-term goal of foreign investment and more domestic investment and a strengthened private sector."
Over the past year, the Crown Prince has become the decision-maker on military, foreign, economic and social policies.
His "Vision 2030" plan includes cuts in government assistance, raising taxes, sales of state property, an efficiency campaign and efforts to gain foreign investment.
Much of Saudi Arabia's largely young population has supported the plan. Older and more conservative members of Saudi society, including parts of the Al Saud royal family, were angered by the Crown Prince's quick rise to power.
Saudi Arabia recently announced it would end its ban on women drivers by June 2018. The decision is part of the Crown Prince's efforts toward social reform. Conservative clergymen with large followings have criticized movement toward such reforms.
As defense minister, Muhammad bin Salman led Saudi Arabia into a now two-year-old war in Yemen. The Saudi government says it is fighting Iran-backed Houthi militants there. The conflict has caused a dispute between Saudi Arabia and Qatar.
On Monday, Saudi Arabia said it would temporarily close all its air, land and sea ports to Yemen. The move came after Saudi forces shot down a missile fired at Riyadh.
I'm Caty Weaver.