An explosion has derailed a freight train for the second day in a row in a Russian region bordering Ukraine, sending both the locomotive and some cars off the tracks, authorities said.
Russian territory and Crimea, annexed by Moscow in 2014, have been hit in recent days by a series of attacks.
The last four days have seen two trains derailed by explosions, a suspected drone hitting an oil depot in Crimea that caused a huge blaze and power lines blown up near Saint Petersburg.
