Hong Kong (CNN Business) Uber is facing a new legal challenge Down Under.

More than 6,000 taxi drivers and car-hire operators are suing Uber in Australia, signing on to a major class action lawsuit. The suit alleges that Uber defied regulations and operated illegally in Australia, giving it an unfair advantage over local taxi drivers and other industry players that complied with the law.

Australian law firm Maurice Blackburn said it filed the case in the Victorian Supreme Court on Friday.

"Uber sells the idea that it does things differently, but in reality and as we allege, this has meant operating unlawfully, using devious programs like 'Greyball,'" Maurice Blackburn lawyer Elizabeth O'Shea said in a statement.

Australia, China and South Korea, according to The New York Times, which first Uber said at the time that the software wasn't meant to target regulators, but to protect its drivers. After the Times report, the company Greyball was a software program that prevented regulators and law enforcement from monitoring Uber's app. Uber used it in countries around the world, includingAustralia, China and South Korea, according to The New York Times, which first reported on Greyball in 2017.Uber said at the time that thesoftwarewasn't meant to target regulatorsbut to protectitsdrivers.After the Times report, the company prohibited the use of Greyball to target local regulators.

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