Eleven princes, four ministers and several former ministers were arrested in Saudi Arabia on Saturday soon after an anti-corruption committee was formed by royal decree, state media reported, quoting unidentified officials.

Those arrested include prominent billionaire investor Prince Alwaleed bin Talal, the National Guard head Prince Meteb bin Abdullah and Economy Minister Adel Fakeih. Prince Alwaleed bin Talal is one of the world’s richest men and holds major stakes in News Corp, Citigroup and Twitter.

No official explanation was given for the arrests.

An airport used for private flights was also closed, which led to speculations that the kingdom wanted to block rich businessmen who might want to flee fearing arrests, The New York Times reported.

The committee can investigate, arrest, ban from travel, freeze accounts and track funds and assets of individuals involved in corruption practices, Al Arabiya reported. Crown Prince Mohammed bin Salman heads the committee, according to the decree that came into effect earlier in the day.

Mohammed bin Salman is considered the favourite son of King Salman, and has been behind several reform measures the kingdom has taken in recent years. The arrests and crackdown on corruption are seen by some as an attempt to consolidate Mohammed bin Salman’s power.

The committee said it will reopen the file of the 2009 Jeddah floods and investigate the government’s response to the Corona virus issue in 2014.