Russia’s southern Belgorod region bordering Ukraine came under attack from Ukrainian artillery fire, mortar shells and drones Friday, authorities said, hours after two drones struck a Russian city in a region next to the annexed Crimea Peninsula.

The Kremlin’s forces, meanwhile, struck a clinic in Dnipro, in central Ukraine, killing a 69-year-old passerby and wounding 23 other people, including two children, Ukrainian officials said. Also, a Russian S-300 missile hit a dam in the Karlivka district of Ukraine’s eastern Donetsk province, placing nearby settlements under threat of severe flooding.

The Belgorod town of Graivoron, about four miles from the Ukrainian border, was under fire for several hours, with four houses, a store, a car, a gas pipeline and a power line damaged, Gov. Vyacheslav Gladkov reported.

Closer to the border, a recreation center, a shop and an uninhabited house sustained damage in the village of Glotovo. There were no casualties, according to Gladkov.

Earlier this week, the Belgorod region was the target of one of the most serious cross-border attacks from Ukraine since the war began 15 months ago. Details of the raid were murky. Russia blamed the Ukrainian armed forces, but two Russian groups said they were involved, with the aim of bringing down Russian President Vladimir Putin.

Officials in Russia’s southern city of Krasnodar, in the region of the same name bordering Crimea, said that two drones struck there. Witnesses told local media they heard something like the sound of a moped and then two explosions.

“There is damage to buildings, but essential infrastructure was not damaged. And most importantly, there were no casualties,” Krasnodar regional Gov. Veniamin Kondratyev wrote on Telegram.

Krasnodar Mayor Yevgeny Naumov said a residential building and an office building were damaged, but there were no casualties.

Drone attacks against Russian regions on the border with Ukraine have been a regular occurrence since the start of Russia’s full-scale invasion of Ukraine in February last year, with attacks stepping up last month.

Earlier this month, an oil refinery in Krasnodar was attacked by drones on two consecutive days.

In another apparent incident of Kyiv’s forces harassing Russia, Ukraine’s defense ministry on Thursday published footage that appeared to show an unmanned drone boat attacking Russia’s Ivan Khurs reconnaissance ship in the Black Sea.

The video didn’t show the drone hitting the ship.

The video followed reports by Russia’s Ministry of Defense on Wednesday that Ukraine had launched an “unsuccessful” attack on the Ivan Khurs using three unmanned speedboats, with all three boats attacked and destroyed prior to reaching the ship. Moscow released footage allegedly showing the destruction of one of the uncrewed boats.

At least two civilians were killed and three others wounded in Russian attacks on Ukraine over the previous 24 hours, the Ukrainian president’s office reported Friday.