Russian forces fired cruise missiles at the southern Ukrainian city of Odesa and shelled the eastern Donetsk region early Wednesday, killing at least six people and damaging dozens of homes, regional Ukrainian officials said.

Russian forces have recently stepped up aerial strikes in their nearly 16-month war, a Ukrainian military spokesman said. The country’s armed forces, meanwhile, have reported limited gains in the early stages of a counteroffensive to take back nearly one-fifth of Ukraine’s territory that is under Russian control.

The grinding Ukrainian advance is pressing slowly ahead, Ukraine’s Deputy Defence Minister Hanna Maliar said on Wednesday. Western analysts and military officials say the effort to dislodge entrenched, powerfully armed and large numbers of Russian troops could take years.

Ukrainian troops have advanced 200-500 metres at various sections of the front line around the Donetsk city of Bakhmut and 300-350 metres in the southern Zaporizhzhia region, Maliar claimed. Ukrainian forces have managed to make gains despite the Russian edge in artillery and air power, she said.

It was not possible to verify the battlefield claims.

Ukrainian forces can expect to make slow progress in what will be a “hugely difficult” fight as the counteroffensive gains traction, according to a Western official, who spoke on condition of anonymity to discuss intelligence.

A Ukrainian police officer inspects the scene of the deadly morning Russian rocket attack in Kostyantynivka, Donetsk region, Ukraine. Photo / AP

“Intense fighting is now ongoing in nearly all sectors of the front,” the official said “This is much more than probing. These are full-scale movements of armour and heavy equipment into the Russian security zone.”

The official described the Ukrainian attacks as methodical and said that broadly speaking, “Russian forces have put up a good defence.”

In Odesa, three food warehouse employees were killed in a strike that also damaged homes, shops and cafes in the city’s downtown, the regional administration said on Facebook. An additional 13 people were injured.

Search teams were looking for possible survivors under the rubble of the warehouse, it said.

The attack on the port city, launched from the Black Sea, was the second in a week and involved four Kalibr cruise missiles, three of which were intercepted by air defences, the administration said.

In eastern Ukraine, Donetsk province Gov. Pavlo Kyrylenko wrote on Telegram that at least three people died after shelling destroyed seven homes and damaged dozens more in the cities of Kramatorsk and Kostiantynivka.

Ten towns and villages along the front line in Donetsk were struck as Kyiv’s troops slowly advance, according to Ukraine’s presidential office.

A missile hit the Ukrainian-controlled city of Kramatorsk, where Kyiv’s forces are headquartered, killing two civilians and wounding two others while damaging 29 homes, the presidential office said. Russian shelling of Kostiantynivka killed one civilian, with 57 houses damaged, it added.

A part of a business centre is damaged after a nightly Russian rocket attack in Odesa, Ukraine. Photo / AP

Andriy Kovalov, a spokesperson for the General Staff of Ukraine’s armed forces, said the Russian military increased missile and aerial strikes as Kyiv’s forces intensify attacks along the war’s 1,000-kilometre front line and claimed some modest gains at the beginning of their counteroffensive.

In a briefing, he said strikes on the Kharkiv, Donetsk and Kirovohrad regions, in addition to the Odesa region, involved Kh-22 cruise missiles, sea-launched Kalibr cruise missiles, and Iranian-made Shahed drones. Nine were intercepted.

Kovalov said Ukrainian forces had made advances in several sections and fighting was continuing in or near at least two Donetsk province communities.

Britain’s Defence Ministry, which has regularly issued updates on the conflict, wrote on Twitter that southern Ukraine “has often been more permissible for Russian air operations” compared with other parts of the front.

Separately, the mayor of the central city of Kryvyi Rih, President Volodymyr Zelenskyy’s hometown, said the death toll from a Russian strike that hit an apartment building a day earlier had risen to 12.

Emergency workers extinguish a fire after a Russian rocket hit in a storehouse building in Odesa, Ukraine. Photo / AP

Ukrainian authorities continued to rescue people from the flooded areas of southern Ukraine’s partially Russian-occupied Kherson region following the destruction of the Kakhovka dam last week.

A total of 28 settlements on the Ukrainian-held western bank of the Dnieper River remain underwater, and nearly 2800 people have been taken to safety so far, the presidential office said, adding that the rescue effort was taking place under relentless Russian shelling.

A visit by Rafael Mariano Grossi, the head of the International Atomic Energy Agency, to the Zaporizhzhia Nuclear Power Plant on Wednesday was postponed for security reasons.

He met with Zelenskyy on Tuesday to discuss the perils facing the nuclear plant, which grew more serious after the Kakhovka Dam burst last week.

The plant has been in the crossfire repeatedly since Russia launched its war on Ukraine in February 2022 and seized the facility shortly after.

The largest nuclear power plant in Europe faces “a relatively dangerous situation”, the head of the United Nations nuclear watchdog told journalists in Kyiv on Tuesday.

The Ukrainian-controlled areas of the Kherson region came under artillery fire 57 times over the past 24 hours, the presidential office said.

Rumours swirled Wednesday about a relative and close associate of the Kremlin-backed, strongman leader of Chechnya, Ramzan Kadyrov. The reports said that politician Adam Delimkhanov had been wounded – or even killed – in Ukraine.

After Russian state TV reported that the politician had been wounded and Ukrainian Telegram channels suggested that he had been killed, Kadyrov published a photo showing Delimkhanov.

In a photo caption, Kadyrov said that Delimkhanov was “alive and well” — adding that he knew this “from the very beginning,” despite earlier requesting Ukrainian intelligence to provide information on what positions were hit so that he could locate his “dear brother”.

- Jamey Keaten, AP