A former riot-police officer turned hire-car driver in Australia has taken it upon himself to crackdown on UberX drivers operating illegally.

Russell Howarth, founder of the group Arresting Uber, made his first citizen's arrests on a driver in Sydney last week and plans to carry out 10 more this week in an effort to raise awareness of unlicensed drivers transporting passengers illegally through the UberX service.

Uber currently operates in over 200 cities across 45 countries around the world and is continuing to expand internationally despite resistance from local taxi organisations and unions. UberX markets itself as the "low-cost Uber" in which drivers use their own vehicles without the need for a "vehicle for hire" license.

"Uber commits more offences and makes more money than any organised crime group in the world," Howarth told IBTimes UK. "The enormity of the illegal activity of Uber is incredible."

Howarth made his first arrest last week after ordering an UberX car to stop and demanding to see the driver's paperwork. When the UberX driver admitted that he was operating illegally, Howarth informed him that he was a private citizen and was affecting a citizen's arrest.

"It was an attempted publicity stunt," an Uber spokesperson said, after hearing of Howarth's first arrest. "I'm not sure we would have heard if any Uber partners had been arrested, but we have not."

No charges have been formally made against the driver in question but Howarth claims that they may still face ciminal charges that could lead to a fine of up to $110,000 AUS (£60,000) if the case is taken to the Supreme Court.

An online petition started by Howarth in support of his cause has already attracted over 1,000 signatures, and since word of the arrest has spread, Howarth claims to have noticed a small drop in UberX drivers operating in Sydney.

"Uber are going to realise soon that these arrests are the biggest threat it has ever faced," Howarth said. "They seem to have an aloof arrogance that they will get away with it.

"The taxi industry could potentially never recover from the damage incurred from Uber avoiding regulation and the government not stepping in."