Ukrainian drones on Wednesday struck energy and military targets in Saint Petersburg as Russia hosts a major economic forum.

Officials said a number of infrastructure sites were damaged, though no deaths were reported.

What do we know about the drone attacks on Saint Petersburg?

Regional governor Alexander Beglov said "several" facilities were hit on the outskirts of Russia's second-largest city.

Ukrainian officials said the attack aimed to disrupt the high-profile gathering, long known as "Russia's Davos," which President Vladimir Putin is expected to attend, as well as members of Germany's far-right Alternative for Germany party.

The Reuters news agency quoted witnesses reporting thick smoke rising over the edge of the city after the strikes.

Ukrainian President Volodymyr Zelenskyy said the drones had hit the Saint Petersburg Oil Terminal and the Kronstadt military base in the city. He referred to "long-range sanctions," Kyiv's term for its own direct attacks on Russian oil and gas infrastructure.

"Ukraine's plan for long-range sanctions is being implemented exactly as needed to bring peace closer," Zelenskyy said, posting a video of an oil depot ablaze on social media.

How has Ukraine's latest attack affected Russia so far?

Governor Alexander Beglov said "several buildings have been damaged" and clean-up operations were under way, without giving further details.

Authorities had warned residents and visitors of possible drone attacks via text message ahead of the strikes.

Smoke was visible from the venue of the Saint Petersburg International Economic Forum, the flagship event hosted by President Putin that runs through Saturday.

"The Petersburg forum is opening with a nice plume of black smoke in the background after Ukrainian strikes," said Sergiy Sternenko, a Ukrainian Defense Ministry adviser.

Putin is set to speak at the event in Saint Petersburg, his home city, on Friday.

The strikes came just ahead of a visit to Kyiv by NATO Secretary General Mark Rutte, accompanied by the ambassadors of the alliance's member states

Edited by Natalie Muller

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