Federal and local police in Boston are undertaking a painstaking examination of video images and photographs from the site of Monday’s attack, which Barack Obama described as “an act of terror”.
Police appealed for witnesses to send in any images they had of the area around the finishing line of the Boston marathon, as they hunker down for what could be a long and difficult investigation.
In a brief comment yesterday the president said the authorities still did not have “a sense of motive” for what he called “a heinous and cowardly act”. The police did not know whether the two bombs were the work of foreign or domestic terrorists or “a malevolent individual”.
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