Ukraine's capital was subjected to the largest drone attack since the start of Russia's war, local officials said, as Kyiv prepared to mark the anniversary of its founding on Sunday (May 28, 2023). At least one person was killed.

Russia launched the "most massive attack" on the city overnight Saturday with Iranian-made Shahed drones, said Serhii Popko, a senior Kyiv military official. The attack lasted more than five hours, with air defense reportedly shooting down more than 40 drones.

A 41-year-old man was killed and a 35-year-old woman was hospitalized when debris fell on a seven-story nonresidential building and started a fire, Kyiv Mayor Vitali Klitschko said.

Ukraine's air force said that Saturday night was also record-breaking in terms of Shahed drone attacks across the country. Of the 54 drones launched, 52 were shot down by air defense systems.

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In the northeastern Kharkiv province, regional Gov. Oleh Syniehubov said a 61-year-old woman and a 60-year-old man were killed in two separate shelling attacks.

Kyiv Day marks the anniversary of Kyiv's official founding. The day is usually celebrated with live concerts, street fairs, exhibitions and fireworks. Scaled-back festivities were planned for this year, the city's 1,541st anniversary.

The timing of the drone attacks was likely not coincidental, Ukrainian officials said.

"The history of Ukraine is a long-standing irritant for the insecure Russians," Ukraine's chief presidential aide, Andriy Yermak, said on Telegram.

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"Today, the enemy decided to 'congratulate' the people of Kyiv on Kyiv Day with the help of their deadly UAVs (unmanned aerial vehicles)," Popko also wrote on the messaging app.

Local officials in Russia's southern Krasnodar region said that air defense systems destroyed several drones as they approached the Ilsky oil refinery.

Drone attacks against Russian border regions have been a regular occurrence since the start of the invasion in February 2022, with attacks increasing last month. Earlier this month, an oil refinery in Krasnodar was attacked by drones on two straight days.

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