Thousands of Mexico City taxi drivers snarled traffic in the mega-capital on Monday in a protest demanding that the government ban US ride-sharing service Uber.
In response, Uber fired back by offering free cab service "on a day so complicated to move" around the metropolis of 20 million people and four million vehicles.
Taxi drivers on foot and many in their cars blocked the city's main arteries, painting windows with the words "Uber Out" and holding signs reading "Criminals with license plates."
The protesters said the app-based taxi service was costing them between 10 and 50 percent of their work because Uber is exempt from certain taxes and can offer cheaper prices.
"It's completely unlawful. Uber is a foreign company that comes to Mexico to illegally become rich," said Marcelino Cadena, 40-year-old owner of a taxi company.
Taxi drivers pay at least 6,000 pesos ($400) per year in taxes, license plates and other charges to the city government, in addition to a 16 percent tax if clients ask for receipts.
Ernesto Hernandez, 37, said his taxi stand only receives 20 phone calls per day compared to the 70 times it rang before Uber's arrival in August 2013.
Uber has been hit with court injunctions in Belgium, France, the Netherlands and Spain, and has faced protests from taxi firms in numerous other major cities, including London and Brussels.