Two drones damaged an administration building of an oil pipeline in Russia's western Pskov region, the regional governor said Saturday.
The explosion is the latest in an escalating series of attacks in Russia amid the Ukraine offensive.
"Early morning, an explosion damaged the administrative building of the oil pipeline near Litvinovo, Nevelsky district," governor Mikhail Vedernikov said.
Shortly after, he said that, according to preliminary information, the building was "damaged as a result of an attack by two unmanned aerial vehicles."
There were no reported casualties, and an investigation was still ongoing.
The blast took place in the village of Litvinovo, around 10 kilometres (6.2 miles) from the Belarusian border. Unconfirmed reports from Baza, a Russian Telegram outlet with sources in the secret services, said the drones were targeting the Transneft oil pumping station in Pskov.
Baza also reported an attack targeting an oil refinery near Erokhino, in the western Tver region. The Tver region press service said a drone had crashed near Erokhino without injuring anyone, but did not give any more details.
Over the past few weeks, reports of drone attacks in Russia have multiplied, usually in regions bordering Ukraine.
On Friday, two drones damaged buildings in the centre of the southern Russian city of Krasnodar, which had been relatively unaffected. Moscow has blamed Kyiv -- and its Western supporters -- for the escalating number of attacks and sabotage operations, including on the Kremlin.
Ukraine has denied involvement.
The regional governor of Belgorod said on Saturday that his region had come under fire again, a day after reporting dozens of Ukrainian strikes.
There were no casualties in the shelling, which hit Shebekino, around seven kilometres (four miles) from the Ukrainian border, governor Vyacheslav Gladkov said.
This week, the region saw an unprecedented two-day incursion from Ukraine, with Russia using troops and artillery to put it down.