Russia on Friday claimed to have improved its fighting positions around the northeast Ukraine town of Kupiansk, as Kyiv's troops struggle ahead with their counteroffensive in other areas.

Moscow also launched a volley of hypersonic missiles at western Ukraine in an attack that killed an eight-year-old boy in a part of the country that has largely been spared from attacks. 

Kyiv said the strikes hit a house where a family with three children lived near the western town of Kolomiya.

Kupiansk and the surrounding areas of the northeast Kharkiv region were recaptured by Kyiv's forces in September, but Moscow has since pushed back into the region, forcing Ukraine to order civilian evacuations.

According to Moscow's defence ministry, Russian units had "continued offensive operations on a wide front and improved the tactical situation" in Vilshana and Pershotravneve to the east of Kupiansk.

The situation around Kupiansk was "difficult, given the power of the enemy group, but controlled", said Sergiy Cherevaty, spokesman for Ukraine's eastern forces.

Ukrainian officials in Kupiansk on Thursday urged residents in 37 settlements wedged between the town and Russian lines to evacuate the area.

Residents could evacuate to Kharkiv, some 90 kilometres (55 miles) west, where they would have the option to move to safer regions, they said.

Russia's drive in Kupiansk has sought to draw Ukrainian forces away from Kyiv's own counteroffensive.

Ukraine launched its highly anticipated push in June after stockpiling Western weapons, but has struggled to make headway in the face of stiff Russian resistance.

- Missile targets -

Russia on Friday launched four Kinzhal hypersonic missiles at targets in western Ukraine, Kyiv's air force said.

"One Kh-47 missile was destroyed within Kyiv region," the air force said, while the rest were hit near the Kolomyia airfield in the Ivano-Frankivsk region.

"Civilian facilities and infrastructure were hit, and one of the missiles hit a residential area," it said.

On Thursday, a Russian strike in the city of Zaporizhzhia killed at least one and wounded 14, according to Ukrainian officials.

The United Nations said Thursday its staff and other organisations had frequently used the hotel hit by the strike.

The UN's humanitarian coordinator for Ukraine, Denise Brown, said in a statement she was "appalled" by the incident and described attacks on civilian targets like the hotel as "inadmissable".

The Russian defence ministry however said it had hit a temporary base for foreign mercenaries in the city. 

"In the area of the city of Zaporizhzhia, the point of temporary deployment of foreign mercenaries was hit," the defence ministry said in a statement.

It comes after two Russian missiles hit a civilian building housing a pizzeria popular with aid workers and journalists in the eastern town of Pokrovsk earlier this week.

Moscow indicated the target of the strike was in fact a command post of the Ukrainian army in the east of the country.

- Moscow targeted by drone -

In Moscow, officials said they had destroyed a drone aimed at the capital, the latest in a string of attacks on the city in recent days.

A Ukrainian drone was destroyed over the western outskirts of Moscow, the defence ministry said, adding there was no damage or casualties as a result of the incident.

"An attempt by the Kyiv regime to carry out a terrorist attack using an unmanned aerial vehicle on a facility in Moscow was thwarted," the defence ministry said, adding there was no damage or casualties as a result of the incident.

Largely spared in the early part of the conflict, the capital has seen a surge in attacks in recent months.

On Thursday, Russia said it downed two drones headed for Moscow, a day after two others were destroyed on approach.

At the start of this month, an office block in the capital's main business district of Moscow City was struck twice within days by debris from a downed drone strike.

AFP journalists saw police had cordoned off parts of a park in the Karamyshevskaya embankment in the west of Moscow, where debris landed Friday.

"Drones are flying yet again above Moscow, and keeping us in fear a bit," said Artemy Dulisov, a 21-year-old tech student who biked with a friend to see where the drone had fallen.

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