The truck that plowed through a crowded Christmas market killed 12 people and wounded 48 others. The death toll may rise further as some of those injured are in critical condition. Witnesses say people screamed and ran desperately for shelter, as the vehicle drove through a major public square near the Kaiser Wilhelm Memorial Church in downtown Berlin. Police have arrested one person. The motive remains unknown.

Police cordon off streets near the site of a lorry crash at a Christmas market in Berlin, Germany, Dec. 19, 2016.  (Xinhua/Shan Yuqi)