RIYADH (Reuters) – A campaign of mass arrests of Saudi Arabian royals, ministers and businessmen widened on Monday after a top entrepreneur was reportedly held in the biggest anti-corruption purge of the kingdom’s affluent elite in its modern history.

The arrests are the latest in a series of dramatic steps by Crown Prince Mohammed bin Salman to assert Saudi influence internationally and centralize his own power within a hereditary ruling system at home.

The campaign also lengthens an already daunting list of challenges undertaken by the 32-year-old since his father, King Salman, ascended the throne in 2015, including going to war in Yemen, cranking up Riyadh’s confrontation with arch-foe Iran and reforming the economy to lessen its reliance on oil.

Both allies and adversaries are quietly astonished that a kingdom once obsessed with stability has acquired such a taste for assertive – some would say impulsive – policy-making.

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