Ukrainians are fortifying and flooding underground pipes because Russian troops keep trying to crawl or walk in them

"Ukraine's war is starting to go below ground. Russian troops were recently found attempting to infiltrate battle lines in Kharkiv by crawling through an underground pipe, with Kyiv's forces trying to stop them by flooding or fortifying such ducts. Ukrainian observers publicly identified the pipeline tactic last week in Kupiansk, a city in the Kharkiv region that has seen heavy fighting along the front lines."

"DeepState, an oft-cited Ukrainian open-source intelligence group, reported on Friday that Russian troops had used a gas pipe near Kupiansk to sneak past the nearby Oskil River and establish supply lines and drone pilot positions closer to the city. The group's analysts published drone footage of a uniformed soldier dragging a package out of a hole in a forested area. The report was echoed on Russian social media channels, accompanied by a widely circulated video of soldiers crawling through a pipe."

Russian troops used underground gas and water pipelines near Kupiansk to move personnel, establish supply lines, and position drone pilots closer to the front. Open-source analysts and social media circulated footage showing soldiers crawling through pipes and extracting packages from forested exits. Ukraine's General Staff confirmed pipeline use, noted the pipe exit lay outside the city, and stated Kupiansk remains under Ukrainian control. Ukrainian forces have flooded and fortified several pipeline passageways to prevent infiltration. This marks the third known instance of such subterranean tactics since the war began, creating a growing defensive challenge.

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