Ukraine claimed on Friday to have orchestrated attacks on a Russian railway line in Siberia, thousands of kilometres from the frontline, in the latest reported sabotage incidents inside Russian territory.
Russian authorities have reported a number of attacks on transport infrastructure since it launched full-scale hostilities in Ukraine in February last year, occasionally pointing the finger at Kyiv.
"The Russians have fallen into the SBU's trap twice -- another fuel train has exploded on the Baikal-Amur railway," a source in Ukrainian law enforcement agencies told AFP, referring to the SBU security services.
The source said the alleged attack on Friday was a follow-up to an initial explosion on Wednesday night involving a train transiting the remote region of Buryatia.
There was no immediate response from the Russian side to the latest incident, but Moscow confirmed a train crew earlier this week had spotted smoke in a fuel tank and called firefighters to the scene.
Russian business daily Kommersant on Friday cited sources as saying that investigators had opened a criminal probe into Wednesday's incident and that the fire on the train was likely caused by an unidentified explosive device.
"Russian special services should get used to the fact that our people are everywhere. Even in distant Buryatia," the Ukrainian source told AFP.
The source added that the second attack had targeted an alternative route for trains using the same railway -- over the Chortov Bridge -- also in Buryatia.
"This is exactly what the SBU was counting on: as the train was passing over this high 35-metre bridge, the explosive devices planted in it detonated."
The Baikal-Amur railway is over 4,000 kilometres (2,500 miles) long and runs adjacent to the borders of China and Mongolia.
Russia earlier on Friday announced it had detained a dual Russian-Italian national for carrying out sabotage attacks on a railway and airbase, acting under the orders of Ukraine.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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