European countries have tightened security ahead of New Year's celebrations, erecting concrete barriers in city centers and boosting police numbers after the Islamic State attack in Berlin last week that killed 12 people.<br/><br/>In the German capital, Berlin, police closed the Pariser Platz square in front of the Brandenburg Gate and prepared to deploy 1,700 extra officers. In Italy, security checks were set up around the main square in Milan. Trucks were banned from the centers of Rome and Naples. <br/><br/>In Spain, administration have planned to deploy an extra 1,600 police on the New Year weekend in Madrid. Across France, more than 90,000 police including 7,000 soldiers will be on duty for New Year's Eve. Brussels and Austria have also tightened security ahead of New Year's celebrations.