Thousands of Chilean taxi drivers honked their horns and blocked traffic Thursday in a protest against ridesharing service Uber.

Uber's service is not regulated in Chile, but the government considers it illegal. The government responded to the protest saying it is up to Congress to pass a law addressing Uber and another ridesharing app used in Chile, called Cabify.

Long lines of black and yellow taxis filled several blocks along Santiago's main avenue, the Alameda, causing traffic jams in the city of six million.

The cars were decorated with the red, white and blue Chilean flag, and their windshields were painted with the words "Uber, get out."

Taxi drivers complain that Uber amounts to unfair competition, as they have to pay taxes and follow strict regulations.

"We never thought we would attract so many people and co-workers. This shows that we are not wrong," said the head of the national taxi drivers union, Luis Reyes.

The government said it is up to Congress to act.

"We cannot block the apps," said the deputy minister for urban transport, Matias Salazar. "Today, the role of Congress is key."

A month ago, a Chilean court threw out a lawsuit filed by a taxi driver against the government for not suspending Uber.