O'Connor's business was focused on high-rolling gamblers, a sensitive area in China at a time when President Xi Jinping's sweeping corruption clampdown has targeted gambling as a potential way for corrupt officials to launder money.
The detentions of the Crown employees sent a chill through the gambling industry in Asia. The Australian company has reduced its links to China in the aftermath.
Crown declined to comment further, citing court restrictions. The Australian government has said it's providing consular assistance to three detained Australians.
Gambling is illegal in China, except in the territory of Macau. Foreign casinos aren't permitted to promote gambling directly in the country, but they are allowed to promote their destinations more broadly.