Since the beginning of the week, even as attention focuses on the aftermath of the collapse of the Nova Kakhovka dam, it has been clear that Ukrainian forces have intensified their activities along the front line in the south-east. from the city of Zaporizhia. But it is still too early to have a real idea of ​​what is happening and to what extent Ukraine really has its feet on the ground and is trying to make a breakthrough.

On Thursday, the Russian Defense Ministry’s Telegram channel quoted Defense Minister Sergei Shoigu as saying that Ukraine’s 47th Mechanized Brigade had made four attempts to break through Russian lines with up to 1,500 personnel and 150 armored vehicles.

The attacks were repelled, Shoigu said, adding that Ukrainian forces suffered heavy losses in troops and weapons. The ministry released drone video purporting to show a series of attacks on Ukrainian tanks during the same clash.

Instead, on Friday morning, Semyon Pegov – one of Russia’s most widely read journalists and propagandists covering the war, often lumped together as Russian “military bloggers” – reported that Ukraine’s armed forces had advanced south from Orikhiv to the city of Tokmak, in Russian-controlled territory. The situation facing the Russian forces is very serious, he said.

The focus has been on this part of the front line for months, so the increased Ukrainian activity is no surprise. Breaking Russia’s land bridge to Crimea, pushing Russian forces back to the Sea of ​​Azov, is clearly a central military objective for Ukraine. Tokmak is on the road to Melitopol, one of the three major cities controlled by Russia – the others are Berdiansk and Mariupol – which are on the coast.

The Ukrainian authorities have said very little about how things are going. In his Thursday evening speech, President Volodymyr Zelensky described “very tough battles”. He added: “There is a result, and I am grateful to everyone who guarantees the result!”, although it is quite possible that he is referring to the fighting around Bakhmut, which is in a very different from the front line. , and where Ukrainian forces have made limited progress recently.

Another Russian military blogger writing on Telegram, Alexander Kots, has tried to portray Ukraine’s moves in the Zaporizhia region since earlier this week as a failed “Blitzkrieg” attempt.

Vladimir Rogov, a local leader based in Russia, although he also reported that Ukraine had suffered “heavy losses” in “hard fighting”, also urged caution.

“The enemy has not yet committed its main reserves in our direction. Everything has only just begun,” he wrote on Telegram.

CNN cannot independently verify claims made by Russian officials or Russian military bloggers with good sources. But a local Ukrainian commander commanding troops on the same front line dismissed the suggestion that Ukraine had begun its big bid to reclaim territory.

Instead, the commander referred to the thrusts as “force reconnaissance”, operations designed to probe enemy defenses for weak spots and test their combat readiness.

CNN’s Sam Kiley and Olha Konovalova contributed to this article.