12 Mar 2004, MADRID, Spain — Railway workers remove debris from the wreckage of a public train near to Atocha train station in Madrid, March 12, 2004. Spain mourned for at least 198 people killed in Europe’s worst attack in 15 years as investigators tried on Friday to pin down if Basque separatists or Muslim militants were behind the bombs on commuter trains. — Image by © KAI PFAFFENBACH/Reuters/Corbis