Moscow, Rabi'I 29, 1438, December 28, 2016, SPA -- Investigators believe that a malfunction of wing flaps could be behind the crash of the Russian military airplane into the Black Sea on the coast of the Russian city of Sochi over the weekend, the Interfax news agency reported Wednesday. A flight recorder recovered from the aircraft revealed that there could have been a problem with the mechanism controlling the wing flaps. This may have led the plane's crew to misjudge the seriousness of the situation, the news agency cited an undisclosed source close to the investigation as saying. The crash, shortly after take-off on Sunday, is believed to have killed all 92 people aboard. Most of the passengers were members of an esteemed military band, the Alexandrov Ensemble, set to perform for troops in Syria, the flight's destination. Investigators have ruled out terrorism as a likely cause. Authorities have said no trace of any explosive has been found on the recovered remains of victims or wreckage, dpa reported. Russian tabloid Komsomolskaya Pravda published purported excerpts from a recording of the crew from the final moments of the flight: "The flaps, damn it! Commander, we're falling." At least 15 corpses and hundreds of fragments of bodies and the plane, including some sections of its fuselage, have been recovered. A massive search operation across several kilometres is ongoing. Russian authorities have cited the strong current in the Black Sea near Sochi as a reason for the fragmentation and spread of the debris. -- SPA 23:40 LOCAL TIME 20:40 GMT www.spa.gov.sa/w300498