Ukrainian drones hit a large Russian military depot deep inside Russian territory, causing a huge explosion recorded by seismological centers.

In one of the biggest hits in the Moscow military arsenal since the start of the war, Ukraine has claimed to have hit military depots in the city of Toropets, a city in Russia’s Tver region about 380 kilometers northwest of Moscow and about 500 kilometers from the border with Ukraine

Videos and images on social media show the moment of the explosion and huge flames rising into the sky.

The strike was part of a wider Ukrainian drone campaign targeting Russian oil refineries, power plants, airports and military factories, and underscores Kiev’s enhanced capabilities.

Monitoring stations recorded that the explosion had a seismic footprint of 2.7 on the Richter scale.

Ukrainian Pravda reported that the operation was carried out by the Ukrainian security service together with the Special Operations Force. An unnamed Ukrainian security official said the weapons cache contained Russian long-range missiles and guided bombs known as KABs.

The Russian Defense Ministry said 54 Ukrainian drones targeted five regions of western Russia overnight and all were destroyed.

But in a tacit admission of the attack, Igor Rudenya, governor of Russia’s Tver region, said firefighters were trying to contain the fire and that some residents were being evacuated from their homes.