A police officer with his sniffer dog patrols in central Moscow on January 26, 2011, the second day after a suicide bombing at Russia's largest airport as 116 people remained hospitalised. Moscow on Wednesday held a day of mourning for the 35 people killed in a suicide bombing at its main airport as President Dmitry Medvedev headed to Davos to convince investors Russia can defeat terror. AFP PHOTO / ALEXEY SAZONOV (Photo credit should read Alexey SAZONOV/AFP/Getty Images)
