At least one person has been killed in an overnight attack on St Petersburg that successfully targeted two of the city's oil facilities.
The region's Governor Alexander Beglov said fires were being extinguished at the St Petersburg Oil Terminal and the Ruchyi oil depot following the attack, which also injured at least five.
A logistics centre belonging to Ozon - known as Russia's Amazon - and a data centre belonging to Facebook equivalent VKontakte were also hit.
Kyiv has not yet commented on the strikes. Ukrainian President Volodymyr Zelensky said on Saturday morning that Russia had targeted his country's energy sector 76 times since Donald Trump declared an "energy ceasefire" last week.
Ukraine had paused its strikes on Russian oil facilities - which it says are to limit the main revenue stream for Moscow's war effort - for three days after the announcement, while accusing Russia of continuing.
It then resumed strikes earlier this week, drawing the ire of Trump, who called for a truce to facilitate a deal he struck with his Russian counterpart Vladimir Putin to supply diesel.
Ukraine has struck St Petersburg before, though regions closer to Ukraine are threatened more often. The city's oil terminal was last hit in July.
Russia's defence ministry said it had shot down more than 1,000 Ukrainian drones over Russian territory overnight into Sunday.
St Petersburg's governor said 12 apartment buildings and two homes were damaged in the attacks on the city, while Pulkovo Airport was temporarily closed.
He also said mobile internet service disruption was possible.
Social network VK confirmed a drone had targeted its regional data centre, but stressed its services were available "as usual" after users reported outages in the early hours of the morning.
Ozon also confirmed its local logistics centre had been targeted by a drone, sparking a fire.
It said staff were evacuated and no one was injured, and that it was not accepting shipments from sellers at the location "as it is currently serving other operational purposes".
As well as numerous oil facilities across Russia, Ukraine has also mounted strikes aimed at disrupting the Russian economy more broadly. Earlier this month, it launched a series of attacks on Yandex, Russia's largest search engine, that led to service disruptions.
Relations between Washington and Kyiv have frayed since the US struck a controversial deal to import Russian diesel in the hope of bringing down US energy prices, which have skyrocketed during the Iran war, ahead of the midterm elections.
Zelensky suggested the deal was tantamount to the US investing in Russia's war effort.
Trump's decision to temporarily suspend a raft of sanctions against Russia has brought fresh criticism, including from some US Republicans.
Both Russia and Ukraine have been striking one another's energy infrastructure with increasing intensity ahead of the winter, as Moscow's full-scale invasion drags on in its fifth year.
Russia says it hits targets used by Ukraine's military, though the UN noted on Friday that the first two weeks of October had been the deadliest for Ukrainian civilians in years.
Russian strikes on energy facilities have left hundreds of thousands without power, raising concerns about civilians enduring another freezing winter.
Zelensky said on Saturday that tens of thousands of people were still without power. Russia launched nearly 2,700 drones, 1,700 aerial bombs and 66 missiles in the past week, most of which were aimed at energy facilities, he said.