MADRID (Reuters) - Spain’s prime minister on Saturday condemned a series of violent protests in cities across the country against restrictions imposed to curb the surge of COVID-19 after a six-month state of emergency came into effect this week.Riot police shot blank bullets to try to disperse scores of protesters who were setting fire to rubbish bins in Madrid’s main thoroughfare Gran Via. Meanwhile, demonstrators pelted police with rocks and other projectiles in Barcelona in a second night of disturbances in Spain’s second-largest city. In the northern Spanish city of Logroño, about 150 people attacked police with stones, set fire to containers and looted shops, police reported. Riot police were drafted in to quell disturbances in Haro, in the wine-growing region of La Rioja.