The invisible army Putin will face if Ukraine is forced to cede land

 The agent had been watching for weeks, carefully observing the movements of Russian patrols, surveillance blind spots and the irregular arrival of the cargo trains.

Slipping from the shadows, he planted homemade bombs on a railway track used to bring weapons and supplies to Moscow’s troops in eastern Ukraine. “Boom, boom, boom”, he heard as he disappeared into the night.

Recounting his recent mission in occupied Donetsk, the civilian working for the Ukrainian resistance told The Telegraph: “The goal was simple: disrupt transport on that route. I did everything so that the line simply became unusable long enough to stop traffic.”

He knows his brave act isn’t war-changing, but it provided “a bit of extra time for our troops on the other side of the front”. Combined with the efforts of at least 2,000 other agents working for Atesh, a pro-Ukrainian underground resistance network, “it adds up”, the 30-year-old agent said.

His testimony is a rare look inside the dangerous sabotage missions carried out by men and women behind enemy lines to derail Vladimir Putin’s war effort.

“Makiivka is my town. I know who walks where, where the streetlights don’t work, where dogs bark for no reason and I don’t stand out,” the agent added. It is because of exactly this – his intimate local knowledge – that an ordinary civilian has become such a valuable asset in the occupied territory.

It is the “invisible enemy” Putin may not be prepared for if Ukraine is forced to surrender land – including perhaps the rest of the Donbas, under the terms of a peace deal being pushed by Donald Trump, the US president.

Atesh and its agents The Telegraph spoke to argued that a ceasefire will not bring peace but mark a new stage in the shadow war being waged by Ukrainian resistance movements.

“I’m not a soldier and not a hero,” the first agent said, but “this is my land … and we will not let them erase the part of Ukraine that still lives inside people here.”

Atesh (“fire” in Crimean Tatar) has been spying on Russian military movements and disrupting its logistics since it was formed in the summer of 2022 in annexed Crimea. The movement quickly spread across occupied Ukrainian territory and deep into Russia, infiltrating Moscow’s military.

The guerrilla group, which collaborates with Ukrainian intelligence and other resistance networks, has been growing in size and sophistication as the war nears the four year mark, allowing it to go after increasingly high-value targets.

Atesh has turned its attention from observation and small-scale sabotage to targeting Russian communication towers, electronic warfare stations, military cargo trains and oil depots.

“It is important because there is no one sphere of this war, we should act and should win in every sphere, it is important to do everything we can,” a spokesman for Atesh told The Telegraph.

Carrying out their operations is becoming more challenging and riskier. Russia has significantly improved its counter-sabotage efforts, bulking up its police and security forces to ruthlessly track down Atesh agents and other saboteurs, and enforced a brutal climate of fear. In 2024, Russia designated Atesh a “terrorist organisation”. Those suspected of working for it now face up to 20 years in jail.

“But we are becoming more skilled, more experienced and are conducting more complicated sabotage – and we succeed,” the spokesman said.

While the group’s accounts cannot be independently verified, the results are visible – often filmed and quickly uploaded to its Telegram channel – in an effort to encourage more to join. “Most of our agents find us,” the spokesman added.

According to a report last month by Armed Conflict Location & Event Data, an independent conflict monitor, Atesh accounted for more than half the reported sabotage incidents in occupied areas in 2025. In 2024, the partisan group brought the sabotage campaign to Russia, with 32 events attributed to the group in 2025.

With the White House pressuring Kyiv to cede territory as part of a peace deal, Russia could be granted de facto control over the land it occupies, condemning 1.5 million Ukrainians to live under indefinite occupation.

“A ceasefire will only change our focus as we prepare for the next stage of war,” the spokesman said.

“I want Ukrainians in occupied territories to know this is not forever, the occupation will be stopped, but we must fight … Don’t fall for this propaganda and this regime. Stay with Ukraine,” they added.

In the meantime, a key focus is recruiting more Russian soldiers. 

“They are not just contract soldiers, but of all ranks, including veterans, who want to stop Putin’s war,” the Atesh spokesman said.

Having a shadow force inside Russian ranks is essential to the work of Atesh. They blow up checkpoints, set fire to their barracks and trenches and feed Ukraine’s military with critical intelligence to help strike targets.

The Telegraph spoke to a senior soldier serving in the Russian armed forces acting as a double agent for the resistance network.

The man, in his mid-20s, was forcibly mobilised, but quickly rose through the ranks. In response to the horrors he saw fighting and the atrocities he saw committed by his comrades in occupied settlements, he joined Atesh in the spring of 2024.

Since then, the chances of survival at the front have become increasingly bleak, he said. “The battles are becoming increasingly fierce … There are heavy losses on both sides – the biggest on the Russian side.”

His commanders “do not consider their personnel as people, but merely as expendable meat”, he said.

He would not describe the specifics for fear of being identified, but he claimed his riskiest mission yet helped Ukrainian troops “advance five kilometres forward”. 

If true, it would mark a considerable feat in an increasingly static war, where the mass deployment of drones makes movement perilous.