Ukraine says troops advanced over 15 km underground through gas pipelines near Kupiansk

Tunnels under the front

Ukrainian forces are advancing through a Soviet-era gas pipeline north of Kupiansk, the Kharkiv region city that Ukraine retook during its autumn 2022 counteroffensive. The line runs under the Oskil river and consists of a main pipe about 120 centimetres wide with several parallel strands. Russian units had earlier used underground pipelines to infiltrate Ukrainian positions, and Ukrainian troops say they have turned that method against them. A video released in the week before 27 October shows soldiers and ground robots moving through narrow, dark lines, some of them on wheeled boards.

What Zelensky announced

In an address on the evening of 27 October, President Volodymyr Zelensky said Ukrainian forces had advanced more than 15 km underground and that more than 100 Russian soldiers had been eliminated, with more than 30 taken prisoner. He presented these as claims, and the 2nd National Guard Corps Khartiia had first published the figures on 22 October. N-tv noted that they cannot be checked independently. Zelensky also wrote on X that evening that Ukrainian fighters had developed the Russian tactic further and made it more technologically advanced. He framed the result in these words:

“More than 100 Russian occupiers have already been eliminated, and more than 30 have been captured.”

Commander-in-chief Mykhailo Drapatyi, Khartiia commander Ihor Obolenskyi and deputy head of the Presidential Office Pavlo Palisa reported the progress and first results of Operation Veles to Zelensky. Units taking part include the R.U.G assault regiment, the Lava drone systems regiment, Main Intelligence Directorate units including the Freedom of Russia Legion and the Russian Volunteer Corps, and the Achilles drone brigade. Khartiia said on 22 October that its troops had moved underground into the Russian rear, combined that with surface operations and drone strikes, and thereby cut Russian forces off from reaching the rear of Kupiansk.

Operation Veles and the wider front

Zelensky described Operation Veles as the third large Ukrainian offensive of 2026 and said the situation on the front was the best it had been in a long time. He added that it could improve further if Kyiv receives additional air defence. He also cited an earlier airborne operation in the east of the front that he said freed more than 800 square km. In August, he said, an offensive in southern Ukraine had regained control of 26 villages that Russian forces had taken earlier. Operation Vivaldi, carried out north of the fortress belt in Donetsk oblast, was described by him as having freed more than 200 square km.

Russian response and assessment

The Ukrainian General Staff said Russian forces made no attacks toward Kupiansk on Monday, 26 October. The US-based Institute for the Study of War reported at the weekend, citing Russian military bloggers, that the operation could endanger Russian positions and force Moscow to regroup its troops. Obolenskyi said Russia had believed only it could use underground tunnels to bypass Ukrainian defences, and that Ukraine had studied those methods and used them against Russia. The operation is named after the god of the underworld in Slavic mythology. The Khartiia corps claims it has carried out the world's first comprehensive counteroffensive underground.