Saudi Arabia has sacked its top military commanders, including the chief of staff, in a series of late-night royal decrees.
Saudi King Salman also replaced the heads of the ground forces and air defences.
The news was published by the official Saudi Press Agency (SPA) on Monday, but no reason for the sackings was given, according to a BBC report.
They come as the war in Yemen, where a Saudi-led coalition is fighting rebels, is nearing the end of its third year.
Crown Prince Mohammed bin Salman, who is also the defence minister, is believed to be behind various recent shake-ups in the country.
Several new deputies in economic and security-related ministries as well as a handful of new city mayors were appointed, including Tamadur bint Youssef al-Ramah as deputy labour minister, a rare senior post for a woman in the deeply conservative kingdom.
The way Saudi Arabia is run has seen major changes under 32-year-old Crown Prince Mohammed bin Salman, who rocketed to the heights of power from near obscurity after his father became king following the death of King Abdullah in 2015 and is pushing big economic and social reforms, reports Reuters
He is popular with many Saudi youths, who make up the vast majority of the population, but has irked some with his unconventional approach, including a palace coup last year in which he pushed out his cousin to become heir to the throne.
Dozens of prominent Saudi figures, including princes, ministers and billionaires, were also locked up in Riyadh's five-star Ritz-Carlton hotel as the prince led a drive against corruption and abuse of power.