Ukraine said on Monday that Russia had attacked Kyiv with a swarm of "kamikaze drones", in what the president's office said was an act of desperation nearly eight months into Russia's invasion.
An AFP journalist in Kyiv saw drones swooping low over a central district of the capital as police officers fired at them with automatic weapons and smoke rising from explosions across the city.
The attack comes exactly one week after Russia launched a massive two-day salvo of missile strikes over cities across Ukraine that disrupted energy and water supplies nationwide.
"They seem to be hitting us every Monday now," said taxi driver Sergiy Prikhodko, who was waiting for a fare near the central train station in Kyiv.
"It's a new way of starting the week," he told AFP.
Air raid sirens sounded in Kyiv shortly before the first explosion at around 6:35 am (0335 GMT), followed by sirens across most of the country.
"All night and all morning, the enemy terrorises the civilian population. Kamikaze drones and missiles are attacking all of Ukraine. The enemy can attack our cities, but it won't be able to break us," President Volodymyr Zelenskyy said.
Kyiv mayor Vitali Klitschko said a residential building in the central Shevchenkivsky district of the capital had been hit. He said 18 people had been rescued but two people were still trapped under the rubble.
The head of the national railways, Alexander Kamyshin, confirmed earlier attacks "near" the capital's central rail hub.
"We need more air defence systems and as soon as possible. More weapons to defend the sky and destroy the enemy," Zelenskyy's chief of staff, Andriy Yermak, said on social media.
"The Russians think it will help them but it shows their desperation," he also wrote.
The Ukrainian military said Russian drones and missiles were targeting towns and cities across the country. It estimated that Russian forces had fired two missiles and 26 air strikes, and carried out more than 80 rocket attacks.
"In the past 13 hours, the Ukrainian military shot down 37 Iranian Shahed-136 drones and three cruise missiles launched by Russian terrorists," the defence ministry said in a separate statement.
In Kyiv, Klitschko said earlier the drone attacks in Shevchenkivsky district caused a fire and damaged several buildings. He warned residents to take shelter.
"Fire departments are working. Several residential buildings were damaged. Medics are on the spot," he said on Telegram.
"We are clarifying the information about the casualties."
Klitschko also posted a picture of what he said was the charred wreckage of one of the kamikaze drones -- loitering munitions that can hover while waiting for a target to attack.
Zelenskyy last week said Iranian drones were used in Russian attacks on energy infrastructure in several cities, although Tehran denies supplying Russia with weapons for the war.
On October 10, Russian missiles rained down on Kyiv and other cities in the biggest wave of strikes in months.
The attacks killed at least 19 people, wounded 105 others and sparked an international outcry.
Moscow carried out further strikes on October 11, though on a smaller scale, striking energy installations in western Ukraine far from the front.
Russian President Vladimir Putin said the strikes were in retaliation for an explosion that damaged a key bridge linking Russia to the Moscow-annexed Crimean peninsula.
Putin last week expressed satisfaction and said there was no need for further massive strikes on Ukraine "for now".
The Russian president also claimed Moscow was "doing everything right" in its invasion of Ukraine, despite a string of embarrassing defeats.
In southern Ukraine, Kyiv's troops have been pushing closer and closer to Kherson, the main city in the region of the same name, just north of Crimea.
Kherson is one of four regions in Ukraine that Moscow recently claimed to have annexed, and the city of Kherson was the first major city to fall after the Kremlin launched its invasion in February.
Washington last week announced fresh military assistance for Kyiv "in the wake of Russia's brutal missile attacks on civilians across Ukraine".
The new $725-million package included more ammunition for the Himars rocket systems that have been used by Ukraine to wreak havoc on Russian targets.
It brings the total US military assistance to Ukraine to $17.6 billion since the Russian invasion began on February 24.