Catalan pro-secession groups urge renewed street protests

A pro-independence civic group in Catalonia is calling on residents to begin a long-term street protest against Spanish authorities' surprise crackdown on the region's plans to hold a secession referendum.

The Catalan National Assembly's call came hours after Civil Guard police arrested at least 12 people, mostly Catalan government officials, suspected of coordinating the referendum.

The group, a driving force behind the secession movement, urged people to gather at noon Thursday outside the region's justice tribunal and bring tents if needed.

Assembly spokesman Adria Alsina said they would stay until "all the prisoners are released."

Wednesday's arrests triggered demonstrations and some minor disturbances in Barcelona and other Catalan cities overnight.

Regional police had to protect Civil Guard agents as they left one raided building.

Spain says the referendum would be illegal.