A Ukrainian drone sparked a fire at an oil refinery in southern Russia and shelling hit a Russian town close to the border for the third time in a week, Russian officials said on Wednesday.

A day after Russia accused Ukraine of sending drones to attack buildings in Moscow, Ukrainian artillery struck the Russian town of Shebekino about 7 km north of the border with Ukraine’s Kharkiv region, regional Governor Vyacheslav Gladkov said on the Telegram messaging app.

Two people were hospitalized and the shelling smashed windows and damaged roofs of an eight-story apartment building, four homes, a school and other places, he said.

The governor of Russia’s southern Krasnodar region said a drone was the likely cause of a fire that broke out at the Afipsky oil refinery.

The fire was soon put out and there were no casualties, Governor Veniamin Kondratyev said on Telegram. The Afipsky refinery is not far from the Black Sea port of Novorossiisk, near another refinery that has been attacked several times this month.

There was no immediate information on who launched the drone but Moscow has accused Kyiv of increased attacks inside Russia in recent weeks, while Russia has repeatedly pounded Ukrainian cities with drones and missiles.

Reuters was not able to independently verify the reports.

A Moscow-installed coordination center also said on Wednesday that five people were killed and 19 wounded in Ukrainian shelling of a village in the Russian-controlled east Ukrainian region of Luhansk.

The center said on the Telegram messaging service that Ukrainian forces had used HIMARS rocket launchers to attack a poultry farm in the village of Karpaty.