Donetsk is one of four regions in Ukraine that Russia annexed illegally in 2022, months after Moscow launched its full-scale invasion.

Russia’s Foreign Ministry also blamed Ukraine and described the strike as a “terrorist attack”.

Also on Sunday, a fire broke out at a chemical transport terminal at Russia’s Ust-Luga port following two explosions, regional officials said. Local media said the Baltic Sea port, 165km southwest of St Petersburg, had been attacked by Ukrainian drones, causing a gas tank to explode.

The blaze was at a site run by Russia’s second-largest natural gas producer, Novatek.

In a statement to Russian media outlet RBC, the company blamed the fire on an “external influence”, saying operations at the port were paused.

Yuri Zapalatsky, the head of the Kingisepp district on the Gulf of Finland where the port is located, said there were no casualties but the area was on high alert.

Firefighters extinguish the blaze at Russia's second-largest natural gas producer, Novatek in Ust-Luga, southwest of St Petersburg.Photo / AP

News outlet Fontanka reported that two drones had been detected flying toward St. Petersburg on Sunday morning, but were redirected toward the Kingisepp district. AP could not independently verify the reports.

Russia’s Defense Ministry did not report any drone activity in the Kingisepp area in its daily briefing. It said that four Ukrainian drones had been downed in Russia’s Smolensk region, and that two more were shot down in the Oryol and Tula regions.

Russian officials previously confirmed a Ukrainian drone had been downed on the outskirts of St Petersburg on Thursday.

In fighting on the front line, Russia’s Defense Ministry said Moscow’s forces had taken control of the village of Krokhmalne in Ukraine’s Kharkiv region. Ukrainian forces confirmed the settlement had been occupied, but described its capture as temporary.

Ukrainian Ground Forces Command spokesman Volodymyr Fityo said Kyiv’s troops had been pulled back to reserve positions from the village, which had a population of about 45 people before the start of the war.

“That’s five houses, probably,” he was quoted as saying by Ukrainian news outlet Hromadske. “Our main goal is to save the lives of Ukraine’s defenders.”

Recent Russian attacks have tried to find gaps in Ukraine’s defences by using large numbers of missiles and drones in an apparent effort to saturate air defence systems.

The massive barrages — more than 500 drones and missiles were fired between December 29 and January 2, according to officials in Kyiv — are also using up Ukraine’s weapons stockpiles.