Armenia and Russia had a day of national mourning on May 5 for the 113 passengers who were killed when an Airbus airliner plunged into the Black Sea earlier in the week. Flags were flying at half-mast and entertainment events and television programs had been cancelled in both countries to honour the memories of the people who died on board the Armavia airbus. The Armenian Embassy in Moscow has opened a book of condolences. All 113 people on board the Armavia airbus perished in the Black Sea waters on its way from Yerevan to Russia's southern city of Sochi on Wednesday. It is still unclear what caused the plane to go off the radar, but experts suspect that it was either the bad weather, or a technical fault.