Protesters erected burning barricades and set cars ablaze as hundreds of police officers in riot gear used tear gas to disperse demonstrators protesting against the eviction of squatters from a building.
Police moved in "as some demonstrators began grabbing stones and throwing molotov cocktails", Flemming Munch, a police spokesman, said on Saturday.
A bonfire in the street ignited a blaze in a building housing a kindergarten and an adjacent two-story house, but was quickly extinguished and no-one was injured.
Police had been expecting more unrest on Friday night after more than 200 people were taken into custody during clashes on Thursday following the eviction of 35 squatters from a former theatre.
|More than 200 people were arrested |
during Thursday's clashes [EPA]
Police borrowed vehicles from neighbouring Sweden to help control the protests and several shops in the area where Thursday's clashes took place had boarded their windows fearing more violence.
Munch said the situation was "calming down" on Saturday morning but "it has been a rather busy and sad night".
Activists have vowed to keep up protests to win back control of the building.
Jan, a spokesman for the centre, told Reuters news agency that they planned to disrupt traffic in the capital with "pin-point actions creating short breakdowns and disruptions. For example, having a dinner party in the street".
"The struggle will continue for a long time. As long as there is no Youth House in Copenhagen, there will be a fight to get one," he said.
Two authorised demonstrations are also planned for Saturday.
Earlier on Friday, a dozen demonstrators occupied the headquarters of the Social Democratic Party to protest against the eviction and demand that Copenhagen's mayor take action to give the squatters a new house.
They left peacefully after a few hours when police ordered them to vacate the building.
The eviction had been planned since last year, when courts ordered the squatters to hand it over to a Christian congregation that bought it six years ago.
The squatters refused, saying the city had no right to sell the four-storey building while it was still in use.