Possibly, Ukraine will complete investigation into the causes of the crash of the Russian Tu-154 plane, which exploded over the Black Sea on October 4. Sergei Fridinsky, spokesman for the Russian prosecutor's general's office in the Southern federal district, said this on Tuesday. In his words, the version that the plane was downed by a Ukrainian missile is the only one that is being considered by the members of the investigation commission. Fridinsky confirmed that the radar systems had registered the moment of hitting the plane. In his words, the radars fixed both the movement of a certain object to the plane and "the contact between the two points". Most probably, the plane was hit "by carelessness", said the spokesman for the Russian prosecutor's office.