Police have dragged Catalan separatists off roads and arrested 13 during protests as the Spanish cabinet met in Barcelona in both a show of central power and an attempt at negotiation.
Secession supporters used tyres and rubbish to barricade highways from before dawn, and thronged the streets of Barcelona in their thousands, many flying the striped Estelada, the Catalan independence flag that bears a lone star.
Some set off flares and burned an image of King Felipe VI, while police scuffled with masked youths in chaotic scenes.
Emergency services said 32 people suffered light injuries, most of them local police.
More peaceful rallies continued into the evening, with thousands marching along the Passeig de Gracia shopping street, normally a draw for tourists, chanting "Freedom for political prisoners!" and "Independence!".
Many were wearing yellow, a colour that had become associated with jailed separatist leaders.
The decision by Prime Minister Pedro Sanchez to convene his cabinet in Barcelona for the first time since the crisis began underlined Madrid's opposition to full independence for the prosperous northeast region of 7.5 million people.
But it could also help him to secure the survival of his minority government with the aid of Catalonian pro-independence parties in return for more autonomy.
Friday's protests were patrolled by Catalonia's local police force, unlike during last year's illegal referendum when national officers' use of batons and rubber bullets caused an outcry.
Meeting at a 14th-century building on Barcelona's historic sea front, the cabinet approved a handful of symbolic measures for the region, including renaming an airport after Josep Tarradellas, Catalonia's first president following the end of Spain's dictatorship.
Four jailed Catalan leaders ended a hunger strike on the eve of Sanchez's visit, and their party vowed to back his broad plan for the national budget in 2019 and 2020.
Failure to approve the budget could topple the government, raising the possibility of a right-of-centre administration with stronger centralist preferences - a risk some Catalan politicians would prefer to avoid.
Australian Associated Press
