WASHINGTON/MOSCOW/KYIV – Moscow came under the largest Ukrainian drone attack in the past two years overnight, with over 400 unmanned aerial vehicles (UAVs) launched toward the Moscow region.

"From evening until 6:00 am, more than 430 drones were flying toward the Moscow region. Most were neutralized by air defense forces at distant approaches. Thirty-six enemy UAVs were destroyed on approach to Moscow," Moscow Mayor Sergei Sobyanin said Tuesday on social media.

The previous largest attack took place on July 4, when more than 200 drones were launched toward the Moscow region.

There were no immediate reports of casualties or significant damage in Moscow.

Trump: End of conflict close

US President Donald Trump on Monday claimed that an end to the Russia-Ukraine conflict, now in its fifth year, is "much closer than people realize."

"He (Russian President Vladimir Putin) wants to end it, and Ukraine wants to end it. We're in talks, and we'll see if we can get it ended," Trump told reporters. "I think we are getting much closer than people realize."

Trump said his administration has been in contact with both Russia and Ukraine in attempts to end their conflict, which is also on the agenda of the upcoming NATO summit.

Trump is expected to leave Monday evening for the NATO summit in Ankara, scheduled for Tuesday and Wednesday.

24 killed in Russian attacks on Kyiv

At least 24 people had been killed and dozens of others injured in the latest Russian attacks on Kyiv and its surrounding region, Ukrainian authorities said on Monday.

In Kyiv, 16 people were confirmed dead, 58 others were injured, the State Service for Emergencies said.

Search and rescue operations were still underway Monday evening at the sites of destroyed residential high-rise buildings in two districts of the capital, the agency said.

In the surrounding region, at least eight people were killed and 48 others wounded in the latest round of massive Russian attacks, the Kyiv Regional Military Administration said, describing the assault as one of the largest on the region since the start of the conflict.

'Omsk Oil Refinery struck'

Ukrainian drones have struck the Omsk Oil Refinery, one of the largest in Russia, regional Governor Vitaly Khotsenko said in a social media statement.

Khotsenko said that Russian air defense systems intercepted and destroyed the majority of incoming drones. Preliminary information indicated that no fatalities or injuries had been reported. Emergency and operational services were deployed to the site and are currently working in the area.

The Omsk Oil Refinery is one of the largest oil refining facilities in Russia. It can process more than 20 million tons of crude oil a year.

In another event, a Ukrainian drone attacked a cooling tower at the under-construction Kursk Nuclear Power Plant-2 during an overnight attack, Kursk Region Governor Alexander Khinshtein said Monday.

Khinshtein said on social media that 12 Ukrainian unmanned aerial vehicles were detected and neutralized as they were heading toward Kurchatov, where the nuclear facility is located.

He said one drone hit the cooling tower of the plant's second power unit, but the structure has not yet been put into operation.

Despite the impact on the cooling tower, the plant's operational systems were not affected, and there were no reports of casualties or environmental damage, he added. 

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Ukrainian fixed-wing drones

Also on Monday, Russia said that its air defense systems downed 519 Ukrainian fixed-wing drones overnight, while Kyiv reported that a Russian missile and drone attack on the capital left at least 11 people dead and dozens injured.

Russia's Defense Ministry said the drones were shot down over 20 regions, including the Belgorod, Bryansk, Kursk, Kaluga, Leningrad, Moscow, Rostov and Yaroslavl regions.

Regional authorities said a woman was killed in the city of Kerch in Crimea, with several others injured in Crimea and the Yaroslavl region.

In the Kaluga region, a drone strike sparked a fire at an industrial enterprise in the Dzerzhinsky District, with no casualties reported after evacuation, according to Governor Vladislav Shapsha.

Leningrad Region Governor Alexander Drozdenko said 56 drones were shot down over the region, adding that infrastructure at the Luga training ground and near the ports of Ust-Luga and Vysotsk was damaged. No casualties were reported.

Meanwhile, Russia's Defense Ministry said its armed forces carried out a large-scale overnight strike on military-related targets in Kyiv and other Ukrainian regions using drones and long-range precision weapons.

Russia summons Swedish envoy 

Meanwhile, Russia's Foreign Ministry said Monday it summoned Swedish Ambassador to Russia Kristina Johannesson to protest Sweden's failure to ensure the security of Russian diplomatic missions following repeated drone attacks.

The inaction of the Swedish authorities, including law enforcement agencies, amid the continued deterioration of security conditions for Russian diplomatic missions in Sweden was unacceptable, the ministry said in a statement.

The Russian Embassy in Stockholm said earlier that Russian diplomatic facilities in Sweden have been targeted in more than 25 drone-related attacks over the past two years, with the latest incident occurring on Thursday and involving two drones, RIA Novosti reported.

The Russian Foreign Ministry demanded that Sweden take effective measures in line with its obligations under international law to ensure the security of Russian diplomatic missions and personnel.