BARCELONA (Reuters) - Spanish national police began to seize ballot boxes and voting papers from Catalan polling stations, the Interior Ministry said, as some voters began casting ballots in Catalonia s disputed independence referendum on Sunday. Riot police clashed with voters outside a Barcelona voting station, where dozens of police used riot shields to push people back, a Reuters witness said. Would-be voters chanted  we are people of peace  and  we are not afraid . Half a dozen armored police vans and an ambulance stood ready nearby, the witness said.  Elsewhere in the northeastern region, some voting stations opened at 9 AM (0700 GMT) and people began to cast ballots. 
Spanish police seize ballot boxes in Catalan referendum