MADRID (AP) - Two small groups of protesters have clashed in central Barcelona as a unionist demonstration of thousands was getting under way, with people throwing chairs at each other before local police separated them.
It was unclear what sparked the violence on Thursday and who was involved.
Footage obtained by The Associated Press showed chairs flying in both directions, as Barcelona's urban guard and regional police removed a few dozen protesters on each side.
A nearby demonstration led by a group of civil society groups opposing a separatist bid in Catalonia wasn't disrupted.
A separate protest of around 200 supporters of far-right and Spanish nationalist groups ended on Barcelona's Montjuic hill with speeches and the burning of a "Senyera," the unofficial flag that has become a symbol for Catalan separatists.