MADRID (Reuters) - Explosions hit two cities on Spain's north coast on Thursday after a newspaper received a warning call in the name of armed Basque separatist group ETA, and at least one person was injured, officials said. A small bomb exploded in Santander close to a major office of Spain's top bank, Santander Central Hispano, but there were no reports of injuries, officials said. Soon afterwards, police in Gijon reported that an explosion in that city had injured one person, though they could not immediately say whether it was a bomb. Both Santander, a provincial capital, and Gijon are...