Thirty people have been arrested after a third night of rioting in the Sants district of Barcelona. The trouble started on Monday when police forcibly evicted people from Can Vies, a building that has served as an unofficial civic centre for 17 years.

After Wednesday night's arrests more protests have been called for, with further violence expected.

The atmosphere is tense after three days of confrontations across burning barricades between residents and baton-wielding police firing rubber bullets. A television outside-broadcast truck and the excavator used to demolish Can Vies were set on fire and banks have also been attacked.

By Tuesday night the disturbances had spread to other parts of the city, while there were peaceful acts of solidarity elsewhere in Catalonia, and as far away as Valencia and the Balearic Isles. A solidarity march has been called in Madrid's Puerta del Sol.

Can Vies, an abandoned building owned by the city's transport authority, was occupied in 1997 by young people in Sants protesting at the lack of public facilities. It was a symbol of grassroots activity in what is a mostly working-class area.

Asked why it was necessary to demolish Can Vies now, Barcelona's mayor, Xavier Trias, said: "We knew it would create conflict and that's why we've been negotiating for three years but we have to obey the law."

Under the district's urban plan what was Can Vies cannot be built on and will become an open space.

The mayor today has also criticised the chief of the Catalan police for resigning on the morning after the riots began, saying "it's not the moment I would have chosen."

Trias has agreed that an intermediary can negotiate on behalf of the city as representatives of Can Vies refuse to deal with his administration. A spokeswoman for the centre told the Guardian that they would discuss his offer but that it would have been better to negotiate before he had ordered the centre's demolition. In response to government claims that the riots are the work of a small group of troublemakers, she pointed out that Can Vies has the support of more than 200 community associations.

A demonstration has been called for Saturday morning with the intention of rebuilding Can Vies, which has not been entirely demolished. The spokeswoman said that while Saturday's "rebuilding" would be largely symbolic, architects say the building can be saved.

While Can Vies has proved the flashpoint, the intensity and rapid spread of the violence reflects widespread anger and despair, especially among young people, who see little future for themselves and are bearing the brunt of austerity policies.

Above all the crisis and popular resistance has centred on property, first with the housing bubble and since then with the policy of evicting anyone who cannot keep up with their mortgage payments. Centres such as Can Vies – and many more that have sprung up during the crisis – have functioned as help providers for those hardest hit.