Two small bombs have exploded in the historic Colombian city of Cartagena, just hours after US President Barack Obama arrived for a summit there.<br /><br />The devices went off near a bus terminal on Friday evening.<br /><br />Two further bombs exploded in the capital Bogota, close to the American embassy.<br /><br />Police say they may have been planted by leftist rebels.<br /><br />...<br />http://www.euronews.net/