Oops!

 Yahoo News:

Russia accidentally blows up its own supply train, Ukrainian intelligence says

I question whether a smokescreen would be effective since the trains are on well-known tracks.  

See. also:

How Anti-Railroad Mines Could Help Ukraine Sabotage Russia’s War Machine

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Zachary Kallenborn, an expert on military drone swarm technology and an official U.S. Army “Mad Scientist”, has proposed bringing back the anti-railroad mine for the modern age. Writing for Small Wars Journal, a magazine covering intrastate conflict, Kallenborn points out that military use of railroads, first pioneered in the 19th century, is still going strong. Specifically, the Russian army is using railroads to support its invasion of Ukraine, even going so far as to deploy armed trains to protect shipments of soldiers and supplies.

Armies around the world have relied on trains since the mid-1800s. The American Civil War is widely considered “the first railroad war,” with both the Union and Confederacy moving large armies by railroad. A railroad engine could haul much more equipment, day or night, rain or shine, than a horse caravan. Since then, every major war in history has involved the use of trains.

Confederate guerrillas were the first to sabotage trains, blowing up tracks that supported the Northern war effort. In Spring 2022, The Washington Post reported that a secret group of Belarusian railroad workers, saboteurs, and hackers worked to slow down Russian trains supporting Moscow’s drive on the Ukrainian capital of Kyiv. The Belarusians, lacking proper equipment, improvised their acts of sabotage.
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