A missile targeted Kyiv on Saturday without causing casualties but ending nearly two months of relative calm in the Ukrainian capital, while frontline regions fended off waves of drone attacks overnight.
Ukrainian officials also hailed the anniversary of the recapture of Kherson city, the regional capital liberated a year ago in the last major frontline shift.
Ukrainian President Volodymyr Zelensky praised Kherson as a "city of hope" while regretting "revenge" daily shelling by Russia.
"Just between yesterday evening and this morning, (Russia launched) almost 40 drones and rockets... Ballistic attacks against Kyiv, drones, and rockets against Odesa, the Kharkiv region," he said.
Ukraine has been bracing for a renewed aerial onslaught this winter, after systematic strikes on the country's energy grid left thousands without heating or electricity in freezing temperatures last winter.
A missile targeted Kyiv "after a long pause of 52 days," said the head of the Kyiv city military administration Sergiy Popko.
AFP journalists in central Kyiv had heard two strong explosions and saw trails in the sky at dawn.
Air sirens had sounded soon after that.
The air force said it destroyed a missile approaching Kyiv -- either an Iskander ballistic missile or an S-400 anti-aircraft missile -- without reporting casualties.
Air defences last downed a missile in Kyiv on September 21. The falling debris wounded seven people, including a child.
Two missiles hit a field between two settlements in the wider Kyiv region, damaging five private homes, said regional military administration chief Ruslan Kravchenko said.
The air force said it downed 19 of the 31 attack drones launched by Moscow between Friday evening and Saturday 03:00 am (0100 GMT).
"The Russian occupants sent most of the attack UAVs to the frontline areas," it said.
It added Russia fired several missiles overnight, but did not specify if any were downed.
Two missiles hit Odesa, wounding three people including a 96-year-old woman who was hospitalised.
Ukrainians have worried that Russia may pick up its campaign of strikes on energy infrastructures, and warned Kyiv would strike back on Russian oil and gas infrastructure.
Energy Minister German Galushchenko said it "would be fair" to target Russia's oil and gas infrastructure if Ukraine's power grid came under sustained attacks, in an interview with Politico.
To prepare for the possible attacks on energy facilities -- for a second winter -- Zelensky said Tuesday Ukraine had deployed more defence systems.
'City of hope'
Zelensky also praised his country's resilience in a message congratulating residents and soldiers for the liberation of Kherson, the capital of the region of the same name.
"Ukraine always comes back -- always!" Zelensky said, adding, "when we are united. And when we unite others."
Ukrainian forces liberated the southern city of Kherson last November, routing Russian troops in an embarrassing defeat for the Kremlin.
Russian forces based across the river from Kherson city still control swathes of territory and shell towns and villages they retreated from.
Two people died in Kherson and eight others were wounded over the past day, governor Oleksandr Prokudin said.
Russian troops also struck the central part of Kherson in the afternoon, wounding two people, the regional administration said.
On the ground, Ukrainian forces are facing assaults from Russian troops around the eastern frontline town of Avdiivka.
"Our servicemen and women are steadfastly holding the line in the Avdiivka sector," Ukrainian army commander Oleksandr Tarnavskyi said.
Ukrainian officials said earlier this week they were bracing for a third wave of attacks from Russian forces, which began storming Avdiivka about a month ago.
Further north in the city of Toretsk, two elderly people died "probably as a result of artillery fire", according to Ukraine's Prosecutor General.