Investigators say heavy rain is to blame for the crash of an Armenian jet which plunged into the Black sea off the Russian coast, killing all 113 passengers and crew on board.Rescue workers in motorised dinghies scoured the area for survivors but a ministry spokesman has said preliminary information was that everyone was dead. Dozens of bodies have been retrieved from the water by, along with numerous body parts, and wreckage of the Airbus A-320. The plane, operated by Armavia, had been making a short flight from the Armenian capital Yerevan to Sochi, a popular holiday resort in southern Russia.According to the Russian foreign ministry, 26 of the passengers held Russian passports, and almost all of the others were Armenian nationals. Passengers relatives, hoping to collect victims bodies gathered at Sochi airport, huddling round a list of victims posted in the terminal.A day of mourning has been declared in Armenia. According to an official, the aircraft had initially been refused permission to land because of torrential rain, but airport staff then changed their minds. The crash occured as the crew made a second attempt to touch down in Sochi airport.