On November 4, Saudi Arabia’s newly formed anti-corruption committee arrested at least 17 princes and top officials. The list of those arrested includes Prince Alwaleed bin Talal, who owns 95 percent of Kingdom Holding, an investment company that holds stakes in companies such as Apple, Twitter, Citigroup, and News Corporation.

In addition to the princes, at least 38 former, current, and deputy ministers in Saudi Arabia were arrested on accusations of corruption.

“Nobody, a prince, minister, or businessman can operate outside the law,” said an aide close to Crown Prince Mohammed bin Salman. Bin Salman is leading the way when it comes to transforming Saudi Arabia’s economy and rooting out corruption.

“People should now realize there’s a red line when it comes to corruption,” the aide added.

The crown prince says he wants to end an “addiction” to oil. He’s started doing so by introducing subsidy cuts and new taxes, among other initiatives.

“If you’re going to tax the average Saudi during this period of reform, then it’s time to clean our own house, princes and all,” said another aide to the crown prince.

The Crown Prince is hoping to give a boost to the nation’s economy, which has stagnated following a crash in oil prices. Some experts say that cleaning up its act could help Saudi Arabia be more competitive for business. The country needs foreign investors to balance its books, buy shares in its oil company Aramco, and help diversify its economy.

“I can assure you that the Kingdom of Saudi Arabia takes very seriously the issue of corruption, waste, and mismanagement,” Saudi Foreign Minister al-Jubeir told CNN. “We want companies to know that when they come to compete in Saudi Arabia they compete fair and square with any other company, and not be subject to people using their influence or position in order to extract better deals.”

U.S. President Donald Trump praised the move. “I have great confidence in King Salman and the Crown Prince of Saudi Arabia, they know exactly what they are doing,” he tweeted. “Some of those they are harshly treating have been ‘milking’ their country for years.”

Sheikh Saud al-Mojeb said that “phase one” is now complete. “A great deal of evidence has already been gathered, and detailed questioning has taken place,” he said in a statement. “All those suspected to date, will have full access to legal resources, and the trials will be held in a timely and open manner for all concerned.”