“Extremely fierce battles” are raging in many parts of Ukraine as Kiev’s forces continue to counterattack, the country’s deputy defense minister said.

Hanna Maliar wrote on Telegram that Ukrainian forces had advanced near Bakhmut to the east and Zaporizhzhia to the south.

However, she acknowledged that Russian forces were strengthening their defenses in some areas.

Her comments come after another night of Russian missile and drone attacks on cities across Ukraine.

Russia has stepped up its bombing campaign in recent weeks, although President Vladimir Putin admits that his forces are short on missiles and drones. The latest wave includes a relatively rare attack on the Black Sea port city of Odesa.

Kyiv’s much-anticipated move has long been taken, and Ukrainian officials have accused Russia of increasing attacks in recent weeks to distract attention from the attack.

Ukraine says its troops have recaptured seven settlements and at least 90 square kilometers (35 square miles) since the start of their counteroffensive.

Maliar wrote on Telegram that the Ukrainian army had advanced around the city of Bakhmut, which has long been the center of a fierce and bloody street-by-street battle with Russian forces.

She said the soldiers advanced 200m to 500m towards the city, as well as 300m to 500m in the southern province of Zaporizhzhia. The BBC was unable to independently verify these claims.

But she acknowledged that the counter-offensive led to some “extremely fierce battles”, as Ukrainian forces tried to break through solid Russian defenses.

Senior Western officials have warned against the idea that Russian forces will simply “melt” in the face of Ukraine’s attacks, adding that Kiev’s interests have “come at a cost” expensive”.

“Russian forces have generally established a good defense from their well-defended and prepared positions and have fallen back between the front lines,” the sources said.

“This ‘mobile defense method’ is proving challenging for the Ukrainians and also costly for the attacking forces. Therefore, progress at the moment is slow,” they commented and said. It is too early to say how effective the Ukrainian attack was.

However, they stressed that heavy losses were possible, given that Russia had months to prepare its defenses.

“This will never be without risk,” they said. “What we are seeing is not unexpected. It is difficult and will be challenging for the Ukrainians. However, what we have seen is that they have continued to overcome places where they have lost, and then keep moving forward. So overall is on the right track.”

Both sides have reported growing casualties among their opponents that cannot be independently verified.

Ukrainian officials said Wednesday night’s air strikes on the Black Sea port city of Odesa killed at least three people.

Another 13 people were injured in the early morning attacks, which targeted a warehouse and damaged shops.

This southwestern city was important for Ukraine’s grain exports through the Black Sea and was frequently hit by rockets during the war.

Military commanders said Russia fired 10 missiles and 10 drones overnight, most of which were shot down by air defenses.

They added that three of the four KH-22 missiles launched from a Russian warship in the Black Sea were shot down, the last of which hit Odesa.

Oleg Kiper, head of the region’s military administration, said the three people killed were workers in the warehouse, which was used as a food storage center.

“There may be people under the rubble,” he added. Mr. Kiper wrote on Telegram that many civilians were injured after the explosion and “air combat” damaged shops, restaurants – including a McDonald’s – and residential areas.

Elsewhere, attacks on the eastern cities of Kramatorsk and Kostiantynivka killed three more people and destroyed dozens of residential homes, Ukrainian authorities said.

And six people – including four forestry workers – were killed after Russia shelled a truck in northeastern Ukraine on Tuesday. Ukrainian prosecutors said the attack took place near the village of Seredyna-Buda, close to the Russian border.

The director of the United Nations nuclear watchdog has postponed a scheduled trip to the Zaporizhzhia nuclear plant.

Senior Ukrainian officials say Rafael Grossi has agreed to postpone his trip until it becomes safer to travel. The director of the International Atomic Energy Agency (IAEA) said on Tuesday he was “very concerned” that the plant could be entangled in counter-attacks from Ukraine.

His officials also stressed that they needed to access a site near the plant to check water levels, after a nearby reservoir that provided cooling tanks for the plant was affected by the destruction of the Kakhovka dam. .

Meanwhile, in Moscow, the State Duma [parliament] passed a new bill allowing the defense department to contract convicted criminals to fight in Ukraine.

The new law will allow anyone who is being investigated for a crime, is being tried in a court of law or who has been convicted but before the sentence takes effect, to register for military service.

Those accused of sex crimes, treason, terrorism or extremism will be excluded from the law.

The move – seen by many as Russia’s latest attempt to avoid a full draft – seeks to fill the void left by growing casualties.