At least one person has been killed and 32 injured following a terrorist attack in the Spanish city of Barcelona, in which a van drove into pedestrians in the area of Las Ramblas, a tourist-heavy spot in the city center, late Thursday afternoon. As tragic details of the incident continue to unfold, notable figures across Spain and the rest of the world have taken to social media to express their sadness to hear of yet another terrorist attack on European soil this year.