Explosions were heard in Ukraine's capital Kyiv, where the city's mayor said five people had been injured by falling debris from downed drones.

Blasts also hit Kharkiv, Kherson, Odesa and Mykolaiv, officials said.

It marks the fourth attack in eight days on Kyiv, and comes just 24 hours before Russia celebrates Victory Day.

The annual holiday commemorates the Soviet Union's victory over Nazi Germany during World War Two, a conflict the Kremlin has baselessly tried to draw parallels to since launching its invasion of Ukraine last year.

After a lull in Russian attacks on civilian targets in recent months, which saw Kyiv go days without an attack, Moscow has intensified its air raids over the past week ahead of an expected Ukrainian offensive in the south-eastern Zaporizhzhia region.

The Ukrainian military said Monday morning's raids, which lasted more than four hours and were launched shortly after midnight, saw 16 missiles fired at targets across the country.

It said that 61 airstrikes and 52 rocket salvos were also fired at cities and military positions. Officials added that some 35 Iranian-made Shahed kamikaze drones had been destroyed. The BBC has not been able to verify these numbers.

In Kyiv, emergency services responded after drone wreckage fell on a runway at Zhuliany international airport - one of the city's two commercial airports - Kyiv's military administration said.

And civilians were injured after drone debris hit a residential building in the central Shevchenkivskyi district, the administration added.

Elsewhere, in the Black Sea port city of Odesa, a warehouse was set ablaze after eight missiles were fired at targets by Russian bombers, officials said. Local media reported that three people were missing after the strikes.

In images posted to social media by Serhiy Bratchuk, spokesperson for the Odesa military administration, flames could be seen engulfing the building, which he identified as a food warehouse.

In Zaporizhzhia, the head of the Russian installed administration Vladimir Rogov said Russian forces hit a warehouse and Ukrainian troops' position in the small city of Orikhiv.

On the eastern front, the Ukrainian commander of forces in the besieged eastern city of Bakhmut said Russian troops had stepped up shelling, in a bid to take the city by Tuesday's celebrations.

Russian troops and fighters from the Wagner Group, a private military company, have been trying to capture Bakhmut for months - despite its questionable strategic value.

Over the weekend, Wagner's founder Yevgeny Prigozhin appeared to U-turn on a threat to withdraw from the city after he was promised fresh ammunition supplies by the defence ministry in Moscow.

Meanwhile, Ukrainian President Volodymyr Zelensky announced that 9 May will be celebrated as Europe Day from now on, in a pointed rebuke to Russia.

Mr Zelensky said he had signed a decree that the day would commemorate European unity, and the defeat of "Ruscism" - a term that is shorthand for "Russian fascism".