Thousands of pro-independence protesters angry about Spain's Cabinet holding a meeting in Catalonia blocked roads across the region Friday and clashed with riot police in its capital.
Grassroots separatist groups and unions called the protests to show their disgust at Spanish Prime Minister Pedro Sanchez's decision to lead his weekly Cabinet meeting in Barcelona.
The Catalan regional government, formed by a coalition of pro-secession parties, is also supporting peaceful protests despite an agreement with central authorities to find a way out of the political crisis that has festered since Catalonia's failed secession attempt last year.
A crowd of mostly young protesters jeered "Go away! Go away!"
The regional Mossos d'Esquadra police force said that one of four protesters arrested for public order offences carried material to manufacture Molotov cocktails.