By Henri Astier BBC News
This video can not be played
Footage appears to show smoke rising from an area in Sevastopol where Russia's Black Sea fleet is based
Russian forces in Crimea have been targeted by a fresh drone strike.
The Russian-appointed regional leader said a Ukrainian drone targeting Russia's Black Sea fleet in the city of Sevastopol was shot down on Saturday.
It follows a string of attacks on Russian forces and installations in the annexed peninsula this month.
Meanwhile Ukraine's president has welcomed a deal allowing UN inspectors to visit the Russian-held Zaporizhzhia nuclear plant, further north.
Early on Saturday a video showed smoke rising from the area in Sevastopol where Russia's Black Sea fleet is based. The BBC News has not been able to independently verify the footage.
The Russian-installed governor, Mikhail Razvozhayev, played down the seriousness of the incident.
He said the fleet's air defences had been activated and the Ukrainian drone destroyed. "It fell on the roof of the headquarters," he said. "There was no significant damage and no-one was hurt."
Later on Saturday, Mr Razvozhayev said anti-aircraft systems had again been in operation in Sevastopol, but gave no details.
Several drone attacks have been reported in Crimea in recent days, including one on an airbase near Sevastopol on Thursday and another on the harbour on Friday.
Earlier in the month nine Russian jets were destroyed in an attack on the Russian military base at Saky, on Crimea's western coast.
Footage on social media at the time showed crowds of Russian tourists fleeing a nearby resort.
Crimea was invaded and annexed by Russia in 2014, and Ukraine has vowed to retake it.
However the Kyiv government has not confirmed or denied involvement in the recent attacks.
Moscow has blamed sabotage for some of them, indicating some kind of special military operation perhaps by Ukrainian forces - or those loyal to Kyiv.
Western officials say these incidents are having a major operational and psychological impact on Russian forces.
In another development, Ukrainian President Volodymyr Zelensky said the safety of the Zaporizhzhia nuclear plant could start to be restored with a visit of international inspectors.
He was speaking after Russia's Vladimir Putin said Moscow would grant UN inspectors access to the facility, north of Crimea.
The Kremlin and Kyiv have blamed each other for shelling the plant over the past week, raising fears of a nuclear catastrophe.
Meanwhile Russia has pressed on with its tactic of overnight shelling of cities, targeting Kharkiv, Dnipro and Mykolaiv, among others.
And the Russian-installed mayor of Mariupol reportedly survived an assassination attempt.
A Russian state TV reporter said the mayor, Kostyantyn Ivashchenko, was in a car when an explosive device went off at the entrance to the city's zoo.
Also on Saturday, UN Secretary General Antonio Guterres held a press conference in Turkey after another two grain ships left Ukraine.
He said he had been "deeply moved" watching a ship carrying grain heading to the Horn of Africa and that such deliveries provided "urgently needed relief for those suffering from acute hunger".
The safe passage of the vessels has been enabled through UN-brokered deals with Turkey, Russia and Ukraine last month.
Mr Guterres added that enabling the transport of food and fertiliser from Russia is also critical as the cost of living crisis deepens.
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