Russia is lobbing North Korean-made ballistic missiles at Ukraine from positions just north of the Russia-Ukraine border.

The missile attacks, apparently involving KN-23 solid-fuel rockets, may have caused significant damage. At least one open-source analyst believes Russia’s new North Korean missiles struck a pair of Ukrainian army logistics bases in recent days, destroying as many as 10 valuable tanker trucks.

Russia’s acquisition of KN-23s—7,500-pound, solid-fuel rockets with 1,100-pound warheads—represents a major escalation of Russia’s 23-month wider war on Ukraine. And Ukraine might not be able to strike back with similar weapons.