Prime Minister Denys Shmyal says the ‘scale of the accident is significant’ after fire at an electrical substation left nearly 500,000 people without power.

Officials warned that repairs could take weeks. The government said it would appeal to Turkey for help and ordered the energy ministry’s stocks of high-power generators to be sent to the Black Sea city.

The CEO of the state grid operator, Volodymyr Kudrytskyi, said critical equipment that had already been damaged several times by Russian missile attacks burst into flames when it could no longer “withstand the load”.

“[The equipment] has been struck so many times that its state leaves much to be desired,” Kudrytskyi told a briefing in Odesa.

He said any further Russian missile or drone attacks could make the situation even worse.

“We will do everything we can for the improvement of the power supply situation to take days rather than weeks,” he said.

Since October, Russian forces have waged a campaign of massive missile attacks on energy infrastructure. Moscow says the raids aimed to reduce Ukraine’s ability to fight; Kyiv has said they have no military purpose and are intended to hurt civilians.

“The situation is complex, the scale of the accident is significant,” Prime Minister Denys Shmyal said on messaging app Telegram. He added that the substation had been “repeatedly” damaged as a result of Russian attacks.

Odesa regional Governor Maksym Marchenko described the accident as “serious,” adding that the energy minister and the head of state-run electricity grid operator Ukrenergo had been sent to the city.

As of Saturday afternoon, about 500,000 people faced outages, he said. That figure represented about half of Odesa’s pre-war population of one million, when it was Ukraine’s third-largest city.

“Today’s power supply [availability] allows to supply the city and the district about 40 or 45 percent, but if we factor in critical infrastructure, then, of course, very little is left for ordinary citizens,” Kudrytskyi said.

The temperature in Odesa stood at 2C (35.6F) on Saturday and is due to dip below freezing for much of next week.

Prime Minister Shmyhal said he had ordered Ukraine’s energy ministry to scramble every available high-power generator in its nationwide inventory and deliver it to Odesa within a day.

He also ordered Ukraine’s foreign ministry to appeal to Turkey to send powerships – vessels that carry power plants – to come to the city’s aid.

At the briefing, Kudrytskyi said the city’s critical infrastructure facilities were now being supplied with power.

Odesa was a favourite holiday destination for many Ukrainians and Russians before Moscow sent troops into Ukraine last February.