Uber cars and police vehicles were damaged by stones thrown during the fighting, which left three police officers injured and led to the nearby United States’ consulate issuing an emergency message to its citizens.

Metered-taxi drivers have regularly targeted Uber drivers in Johannesburg over the last year, with violence erupting outside train stations, bars and restaurants where they compete for passengers.

The Uber car-hailing app service has become hugely popular in the city where public transport is poor and metered-taxi drivers previously had a monopoly.

“Metered-taxi drivers attacked Uber drivers in Sandton and damaged their cars,” said Metro police spokeswoman Edna Mamonyane, adding police who arrived at the scene were also attacked.

“Police had to fire warning shots to free themselves. Three officers got injured.”

One person was arrested for the violence.

Sandton is the wealthy financial district of Johannesburg, and is home to dozens of international companies.

“Shots were fired… during a violent confrontation between the metered taxi associations in Johannesburg and the online transportation network company Uber,” the US consulate said on its website.

“Further incidents are likely near traditional taxi stands around the city, particularly… outside Gautrain stations or at the airports.”

Uber drivers in South Africa, and in many other countries, have faced threats from metered-taxi drivers who accuse them of stealing business and posing unfair competition due to low fares.

Earlier this week, the rival cabbies scuffled outside a meeting in Johannesburg as city authorities launched a process to formally licence Uber drivers.