Bogotá (dpa) - After mass protests against the Colombian government and serious riots in the capital Bogotá a nocturnal curfew has been imposed.

No one was allowed on the street since Friday evening at 9 pm (local time, 3 am CET) until 6 am, said Mayor Enrique Peñalosa Londoño. Exceptions were for air travelers, airport employees and pilots. With the curfew the city administration wants to prevent further riots.

In the south of Bogotá masked demonstrators had last delivered street battles with the police. They hurled stones at the security forces, who in turn fired tear gas and stun grenades into the crowd. Around 20,000 police officers were deployed in the capital.

"Peaceful expression is a right in a democracy, but we should categorically reject any form of violence," said President Iván Duque. "It is our duty to maintain order and to guarantee security. These principles are never abandoned to those who call for hatred and violence. »

The protests started on Thursday, when around 200,000 people took to the streets in numerous South American cities against conservative President Duque's government. The protests address, among other things, planned labor market and pension reforms as well as increasing violence against activists with social concerns.

According to the Department of Defense, three people were killed in clashes in the Valle de Cauca department in the west of the country. In riots on the verge of demonstrations 150 police and 122 civilians were injured. In addition, there were 98 arrests.

Recently, numerous countries in South America were shaken by violent protests. In Bolivia, President Evo Morales resigned after electoral allegations and fled into exile in Mexico. In Chile, after weeks of demonstrations, the government and the opposition agreed to work out a new constitution. In Ecuador, the government had to withdraw the withdrawal of petrol subsidies due to heavy protests.