"There was a right engine failure when flying to Astrakhan, [the plane] is heading back to Vnukovo," the spokesperson said.
According to the flight tracking website FlightRadar24, the Moscow-to-Astrakhan flight turned back to Vnukovo Airport in the Russian capital over the Volgograd region.
The plane took off from Vnukovo at 7:15 a.m. Moscow time, as scheduled, and was flying over the capital region as of 9 a.m. The airport is preparing for an emergency landing.