Local resident gather in a courtyard near a block of flats heavily damaged during conflict in the southern port city of Mariupol on Monday. Reuters

The attacks came as Russian troops captured the east Ukraine town of Kreminna, local authorities said. "There was a major attack in the night" from Sunday to Monday in Kreminna, the Lugansk regional governor Sergiy Gaiday said in a statement on social media. "The Russian army has already entered there, with a huge amount of military hardware ... Our defenders have retreated to new positions," he added.

A woman mourns as medical workers retrieve the body of her father, following Russian shelling, in Kharkiv. Reuters 

Later during the day, Russian strikes killed at least eight civilians in the embattled eastern Ukrainian regions of Donetsk and Lugansk, local authorities said.

Four died as they tried to flee the city of Kreminna where Russian forces have gathered, regional governor Sergiy Gaiday said on Telegram. Four other civilians died in Russian bombing in Donetsk, according to regional governor Pavlo Kyrylenko.

Ukrainian soldiers stand at the remains of the Antonov An-225 world's biggest cargo aircraft at the Antonov airport in Kyiv. AP

In other developments, a few thousand Ukrainian troops, by Russia's estimate, remained holed up at a mammoth steel mill in Mariupol, the last known pocket of resistance in the devastated southern port city after seven weeks of bombardment. The holdouts ignored a surrender ultimatum from the Russians on Sunday.

Earlier on Monday, Russia's defence ministry said it had hit 16 military targets at various locations across Ukraine. Following the attack on Lviv, black smoke billowed from the gutted roof of a car repair shop in the northwest of the city as air raid sirens wailed.

Firefighters work at the site of military strikes on buildings as Russia's attack continues in Lviv. Reuters

"Fires were set off as a result of the strikes. They are still being put out. The facilities were severely damaged," Lviv regional governor Maksym Kozytsky said on social media. "Today we understood clearly that we don't have any safe places in Ukraine. It's very dangerous," a bank employee who gave her name as Natalia told AFP after the strikes.

PUTIN HONOURS BRIGADE

Russian President Vladimir Putin on Monday lauded a brigade accused by Ukraine of committing atrocities near the capital Kyiv as his forces pounded targets across the country, killing at least seven people in the western city of Lviv.

The air strikes in Lviv came just hours after Zelensky accused Moscow of wanting to "destroy" the entire eastern region of Donbas where Russian forces were massing for an expected all-out assault. Despite widespread condemnation of Russia's invasion of Ukraine, Putin appeared to double down on Monday.

The Russian president signed an official decree bestowing the 64th Motor Rifle Brigade the title of "Guards" for defending the "Motherland and state interests" and praised the "mass heroism and valour, tenacity and courage" of its members.

NO HUMANITARIAN TRUCE SOON

 Humanitarian ceasefires between Ukrainian and Russian forces in Ukraine are not on the horizon right now, but may be possible in a couple of weeks, the UN aid chief said on Monday.

Martin Griffiths made the comments in a briefing to reporters at UN headquarters in New York on his attempts to arrange local ceasefires in Ukraine so that desperate civilians could be evacuated from embattled areas and to provide badly needed assistance.

Griffiths met senior officials in Moscow and Kyiv this month to discuss UN "aspirations" for humanitarian ceasefires and ways to improve a system to notify the sides of evacuation and humanitarian supply movements. "Obviously, we have not yet got a humanitarian ceasefire in place on the Russian side," he said. "I went into a lot of details on this and they continued to promise to get back to me on the details of those proposals."

Agencies