Ukraine on Friday claimed responsibility for attacks on a Russian railway line in Siberia, thousands of kilometres from the frontline, the latest reported incident of sabotage on Russian territory.
Russian authorities have suffered multiple attacks on their transport infrastructure since the start of the invasion of Ukraine in February 2022. But this is the first time they have occurred so far from the frontline.
The first attack took place on Wednesday night on the Besolov tunnel in Severomouisk, the longest in Russia, a source in the Ukrainian security forces (SBU) told AFP.
The second targeted an alternative route of the track, to which rail traffic was diverted after the first attack, the source said.
"The Russians fell into the SBU's trap twice: another fuel train exploded on the Baikal-Amur railway track" while "passing over a bridge at a height of 35 metres", he added.
The SBU declined to comment on these claims and there was also no immediate reaction from the Russian side to the latest incident.
The Telegram channel Baza, which is close to the Russian security services and is followed by more than a million users, reported on Friday that "sabotage" had caused explosions on two trains "in the same area" in Buryatia.
Russia announced on Friday that it had arrested a dual Russian-Italian citizen suspected of carrying out sabotage attacks against a railway and an air base on Ukrainian orders.
Investigators opened an enquiry into Wednesday's incident, according to sources quoted by the Kommersant business daily.
"Russian special services should get used to the fact that our people are everywhere. Even in faraway Buryatia," the Ukrainian source told AFP.
The Baikal-Amur line is more than 4,000 kilometres long and runs along the borders of China and Mongolia.