A high-profile economic forum in Saudi Arabia began on Tuesday in Riyadh, the kingdom's first major event on the world stage since the killing of writer Jamal Khashoggi at the Saudi Consulate in Istanbul earlier this month.

The Future Investment Initiative forum is the brainchild of Saudi Crown Prince Mohammed bin Salman, aimed at drawing more foreign investment into the kingdom and to help create desperately needed jobs for its youthful population.

Prince Mohammed was not immediately at the forum when it started.

The forum last year proved to be a glitzy affair that drew more international business attention to the kingdom. This year's event meanwhile has seen many top business leaders and officials drop out over Khashoggi's Oct. 2 slaying.

"As we gather here in Riyadh this morning, it is natural that our thoughts tend to focus on recent events surrounding the death of Jamal Khashoggi — a writer, a journalist and a Saudi journalist known to many of us," said Lubna Olayan, a Saudi businesswoman moderating the forum's first panel. "May he rest in peace."

She added that such "terrible acts reported in recent weeks are alien to our culture and DNA."

"Saudi Arabia is going through a crisis," Saudi Energy Minister Khalid al-Falih said in statements on the sidelines of the conference.

Falih said the murder of Khashoggi was regrettable, adding that "nobody in the kingdom can justify it."

On Monday, the event's website was hacked and defaced with an image depicting the crown prince holding a sword over Khashoggi's head.

The website showed several messages in English, all aimed at Riyadh.

"For the sake of security for children worldwide, we urge all countries to put sanctions on the Saudi regime," the message stated.

"The regime, aligned with the United States, must be kept responsible for its barbaric and inhuman action, such as killing its own citizen Jamal Khashoggi and thousands of innocent people in Yemen. The medieval Saudi regime is one of the sources of #Terrorism_Financing in the world."

The website was briefly taken down before coming back online.

The killing of Khashoggi has marred the prince's standing, especially amid Turkish media reports a member of his entourage on trips abroad allegedly took part in the slaying and made phone calls to the prince's office.

Saudi Arabia, which for weeks maintained Khashoggi had left the consulate, on Saturday acknowledged he had been killed there in a "fistfight." Turkish media reports and officials maintain that a 15-member Saudi team flew to Istanbul on Oct. 2, knowing Khashoggi would enter the consulate to get a document he needed to get married. Once he was inside, the Saudis accosted Khashoggi, cut off his fingers, killed and dismembered the 59-year-old writer, according to Turkish media reports.

The killing has also thrown into question whether Western executives will continue business as usual with the crown prince, who as King Salman's favored son is the second most powerful man in the kingdom.

Last year, the investment forum grabbed headlines when Prince Mohammed wowed the crowd of global business titans with pledges to lead the ultraconservative kingdom toward "moderate Islam." He also announced plans to build a $500 billion futuristic city in the desert.

He spoke on stage alongside Stephen Schwarzman of U.S. private equity firm Blackstone and Masayoshi Son of Japan's technology conglomerate SoftBank.

Schwarzman is among those who've backed out of attending this year. Others include U.S. Treasury Secretary Steven Mnuchin, who met with Prince Mohammed separately before the forum, according to Saudi state television.

Among its many investments domestically and abroad, Saudi Arabia's sovereign wealth fund, which the crown prince oversees, has invested $20 billion in a U.S.-focused infrastructure fund with Blackstone.

The Public Investment Fund has also invested $3.5 billion in ride-sharing firm Uber, whose CEO also backed out of attending this year's forum.

Just days after last year's forum, the emboldened prince launched a sweeping shakedown of Saudi Arabia's wealthiest businessmen and top princes for alleged corruption, transforming the same Ritz-Carlton hotel that had earlier hosted the investment forum into a prison for the country's elite.

The crackdown — a surprise move by the prince, who's upended the kingdom's reputation for slow, cautions reforms — rattled investors.

Alongside moves like allowing cinemas to open and lifting a ban on women driving, the crown prince has led a stifling crackdown on dissent. Dozens of critics and activists have been detained, including several women and their supporters who had long pushed for the right to drive.