Clashes erupted Tuesday as thousands of taxi drivers took to the streets of the Indonesian capital to protest against Uber and other smartphone ride-sharing applications.
Protestors parked their cars on the major streets of Jakarta, causing massive traffic jams and leaving thousands of people stranded.
The drivers waved banners that read "Close Uber and Grab!" and "Stop illegal transport."
The strikers and the drivers of application-based taxi services were involved in street battles in central Jakarta, chasing and throwing rocks at each other.
The protestors also stopped other drivers who were working normally, attacking them and their vehicles. Local media reported scuffles among drivers broke out in several locations.
At least one observer said the initiative would create ill will.
"All this protesting is only going to convince consumers of one thing: traditional companies can't compete and will resort to bullying," said Aulia Masna, a technology writer.
"Taxi and bus drivers complain about unfair competition from transport apps. We the riders complain about public transport being lousy."
Regular taxi drivers said their incomes had dropped by about 60 per cent as customers opted to use Uber and Grab, which offer lower fares.
"We are not against competition, but we want the competition to be fair," said Umar Wahab, a taxi driver.
"Online taxi companies receive millions of dollars from foreign investors and their fares are heavily subsidized," he said.
App-based taxi services often offer passengers rides at low or no cost as part of promotion campaigns.
Jakarta Governor Basuki Tjahaja Purnama said Uber and Grab would be allowed to operate as transport companies if they set up cooperatives and pay tax.
The Transport Ministry's circular in December asking the police to crack down on non-taxi ride-sharing services sparked a public outcry, prompting the president to step in. The letter was revoked hours later.
Jakarta, a city of 10 million people known for traffic jams, does not have a mass rapid transit system and dedicated bus lanes are often clogged with cars and motorcycles.
The city is building a metro system but it will not be operational until late 2018. Road restrictions caused by the construction work has worsened the already serious traffic congestion.