At least 14 people were killed and dozens more injured Monday in a bombing on a trolleybus in the Russian city of Volgograd, the second deadly blast in the city in two days. The attacks come just weeks before Russia will host the 2014 Winter Olympic Games in Sochi, about 430 miles away. There was no immediate claim of responsibility for either attack, and police said they are adding officers to railway stations and airports. But the deputy head of the anti-terrorism unit, Alexei Filatov, told Reuters that the increased security around Sochi is what is driving terrorists to strike in cities like Volgograd. Meanwhile, International Olympic Committee president Thomas Bach insisted after Monday's bombing that they feel "safe and secure" holding the games in Sochi.