MADRID // The Spanish interior ministry says two train stations in the northern Basque region were attacked with small explosive devices, causing some damage but no injuries. A bomb made from a mixture of explosives detonated Saturday at 12.30am local time. It exploded in the ticket hall of the station in Berriz, causing its ceiling to collapse, a regional ministry spokesman said. Then, at 2.30am local time, two Molotov cocktails were thrown at ticket vending machines in the town of Amorebieta, causing regional police to shut the station and cordon it off, the spokesman said on condition of anonymity in keeping with government rules. The attacks took place on the date the Basque regional government was to hold a referendum before it was banned last month by Spain's Constitutional Court.