Russia’s defense minister said today that his forces had repelled the first three days of a counterattack launched by Ukraine, in which more than 3,700 Ukrainian soldiers were killed or wounded in the fighting.

Defense Minister Sergei Shoigu made the claims in an unusually detailed statement citing alleged casualties on both sides. Ukraine has maintained a deliberate vagueness about whether its long-anticipated counteroffensive is underway, and Reuters has been unable to independently verify the claims on the battlefield.

“Over the past three days, the Ukrainian regime launched a long-promised offensive in various sectors of the front,” Shoigu said.

“Attempts to attack were repelled, the enemy stopped,” he added. “The enemy did not achieve their objectives but suffered significant and incomparable losses.”

Shoigu said Ukraine lost 3,715 men in those three days, as well as 52 tanks and 207 armored vehicles. Russia lost 71 soldiers and had 210 wounded during the same period of fighting. Russia lost 15 Russian tanks and 9 armored vehicles, Shoigu said.

Russia announced on Monday that Ukraine had launched its long-awaited counteroffensive in an attempt to break through the Russian front in the southern Donetsk region.

On Monday, Shoigu said, Ukraine attacked at seven points along the front but suffered significant casualties, losing more than 1,600 men.

Ukraine dismissed Russia’s claims as lies but did not provide details about the attacks — or their outcome.

Shoigu blamed Ukraine for the destruction of the Kakhovka dam in the southern part of the country that occurred in the early hours of today, saying it is a cover tactic used by Kiev to redeploy its forces in the region and carry out offensive operations.

“The Kiev regime committed another crime of terrorism: The Kakhovka hydroelectric power station was blown up, flooding significant areas,” Shoigu said.

Ukraine and its Western allies say Russia blew up the dam.