Citizens present flowers to victims at a railway station in Volgograd, Russia, on Dec. 31, 2013. On Sunday, a suicide bomber ripped a railway station in Volgograd, killing 17 people and injuring 45 others. Another bomb went off Monday morning in a trolley bus on the same city, leaving at least 15 dead and 28 others wounded. (Xinhua/Jia Yuchen)