MOSCOW (Reuters) - Buses believed to be carrying Ukrainian prisoners arrived at Moscow’s Vnukovo airport on Saturday, Interfax news agency reported, as a major prisoner exchange between Russia and Ukraine appeared to get under way.

Meanwhile, a plane with Ukrainian government markings landed at the same airport, Interfax said.

Reuters earlier reported that buses had left Lefortovo prison in Moscow, accompanied by a police escort. [L5N25Y05O]