Russian drones have attacked Ukrainian cities and missiles have struck a residential building, as Ukrainian and British military experts predicted that a months-long ground offensive on Bakhmut in the east of the country could be halted after facing fierce resistance.

Sirens sounded in different parts of the capital Kiev and parts of northern Ukraine. Ukraine's military said it shot down 16 of the 21 Iranian-made Shahid suicide planes.

Firefighters battled a blaze in two adjacent apartment buildings in the southern Ukrainian city of Zaporizhia, where officials said at least one person died and 33 others were wounded in a double Russian missile attack.

In Rzhishev, on the banks of a river south of Kiev, Andrey Nepetov, a local police chief, said at least eight people had died and seven wounded after a drone bombed two university dormitories and a college.

Earlier on Thursday, Russian forces launched a wave of air strikes in northern and southern Ukraine, a day after Russian President Vladimir Putin bid farewell to his Chinese counterpart Xi Jinping following a two-day visit to Moscow.

British military intelligence said on Thursday that Russia had partially regained control of roads leading to the eastern Ukrainian town of Kremina after its forces were forced to retreat from the area earlier this year.

"In some places, Russia has made progress of up to several kilometers," military intelligence said in an update to its bulletin, noting that Russian commanders are likely trying to expand a security zone and are seeking to retake the Kobyansk logistics center in Kharkiv.

Ukrainian President Volodymyr Zelensky on Thursday released footage from a visit to the southern region of Kherson, where he vowed to "restore everything" after the Russian war.

A Ukrainian counteroffensive late last year prompted Russian forces to withdraw from Kherson after months of occupation.

On the other hand, the pro-Russian authorities in the Donetsk region said that the continuous Ukrainian shelling resulted in the injury of 6 civilians, as Ukrainian forces shelled yesterday 7 residential neighborhoods with about 150 shells, including a number of neighborhoods of the capital, Donetsk.

According to the authorities, the shelling caused material damage to more than 20 residential and civilian infrastructure buildings in the city.

Battle of Pakhmut

On the situation in the city of Bachmot, the British Ministry of Defence said in an update to its intelligence bulletin on Wednesday that Russia's attack on the city may lose momentum, but noted that there is still a risk that Ukrainian forces may be trapped in Bakhmot.

The Ukrainian military staff agreed that Russia's offensive potential in Pakhmot was declining, saying in a report published Thursday morning: "The enemy continues to launch offensive operations, suffers heavy losses and loses a large amount of weapons and military equipment."

"Ukrainian defenders are repelling many enemy attacks around the clock in the vicinity of Pakhmut, Bohdanivka and Predchen," it said, adding that several communities near the contact line had been shelled.

The commander of the Ukrainian ground forces, Alexander Sirsky, wrote on Telegram: "The aggressor does not despair of controlling Bakhmut at any cost, despite the losses in personnel and equipment."

Russian forces on high mobility in and around Pakhmut "are losing a significant force and are exhausted," he said. Very soon, we will take advantage of this opportunity as we have done before near Kiev, Kharkiv, Balaklia and Kubiansk," he said, referring to previous Ukrainian military victories.

In a show of defiance, Ukrainian President Volodymyr Zelensky's office released a video of him handing out medals to troops he said were near the front line in Bakhmut.

Pakhmot has become a key target for Moscow, which sees the city as a stepping stone towards completing its invasion of Ukraine's eastern Donbas region.

Ukraine's military said 660 Russian soldiers, 13 tanks, an air defense system and 11 armoured personnel carriers had been destroyed the day before.

International organizations estimate that the cost of Ukraine's reconstruction will reach $411 billion, 2.6 times more than the country's gross domestic product last year.