Regional Governor Oleg Synegubov said on Telegram on Saturday three children, aged seven, four, and six months, were among the victims after the strikes hit at least 15 houses, causing large-scale fires.

An overnight Russian drone attack on a petrol station in Ukraine’s eastern city of Kharkiv has killed at least seven people, including three children, the regional governor said on Saturday.

“Unfortunately the death toll from the occupiers’ attacks on Kharkiv has risen to seven,” Oleg Synegubov said on Telegram, adding: “Among them are three children: 7, 4 years old and a baby about six months old.”

Kharkiv mayor Igor Terekhov said earlier that the attack late on Friday night sprayed nearby homes with burning fuel, causing large-scale fires that forced at least 50 people to evacuate. “The enemy’s Shaheds [Iranian-made drones] hit a petrol station, causing burning fuel to spill out and 14 private houses to burn,” he said.

Firefighters and rescuers worked through the night to cope with the consequences of the strike, extinguish fires, and clear through the debris, officials said.

Kharkiv regional prosecutor Oleksandr Filachkov said three drones hit Kharkiv’s Nemyshlyanskyi district.

“As a result, an object of critical infrastructure was destroyed. There was a large amount of fuel, which is why the consequences of the fire were so terrible,” he said, referring to the petrol station.

The Ukrainian Air Force said that air defence and mobile groups of drone hunters shot down 23 out of 31 Russian-launched drones, which were targeting the Kharkiv region and also the Odesa region.

Kharkiv, about 30km (18 miles) from the Russia-Ukraine border, has been under regular attack since Russia’s invasion of Ukraine began in February 2022. The region has been a frequent target of Russian assaults in recent weeks.

On January 23, a barrage of missiles struck Kharkiv and two other Ukrainian cities in one of the heaviest bombardments since the start of the year. Officials said at least 11 people were killed and about 5,000 windows in 222 buildings were broken by the blasts and shockwaves throughout the region.

It marked what the United Nations called “an alarming reversal” of a trend last year that saw a drop in civilian casualties from Moscow’s attacks.

The region with a pre-war population of 1.5 million is Ukraine’s most vulnerable urban centre. Russia lies north and east of it, and the border of Moscow-annexed Luhansk region is about 150km (90 miles) to the southeast.

Since day one of the full-scale invasion in February 2022, Russian forces have tried to seize Kharkiv, dispatching armed personnel carriers almost to the city centre.

Moscow has deployed strategic bombers, ballistic or cruise missiles, and Iranian or Russian-made drones that take just minutes to reach the city from across the border.