Blast intensifies fire at Russian oil depot struck by Ukraine

MOSCOW (Reuters) - An explosion rocked an oil depot in Russia's Krasnodar region where firefighters are trying to extinguish a blaze that broke out after a Ukrainian drone attack earlier this week, regional authorities said on Friday.

"During the extinguishing process, due to depressurisation of the burning tank, there was an explosion of oil products and release of burning oil," officials said on the Telegram messaging app.

The fire spread to another tank, and the fire area increased to 10,000 sq metres (108,000 sq feet), they added - more than twice the original area of the blaze. More than 450 firefighters were trying to tackle it, and two had been injured.

Interfax news agency quoted regional authorities as saying that excess levels of harmful chemicals including benzene, had been detected in atmospheric tests at two locations nearby.

The depot, near the village of Kavkazskaya, is at a rail terminal for Russian oil supplies to a pipeline linking Kazakhstan to the Black Sea.

The challenge of putting out the blaze highlights the disruptive impact of Ukraine's frequent strikes against Russia's vast energy industry, whose revenues fuel Moscow's war effort. Russia too has pounded Ukraine's energy grid throughout the war, causing frequent blackouts affecting civilians and industry.

Russia's foreign ministry said on Thursday that Ukraine had already violated a proposed ceasefire by attacking the depot.

Ukrainian President Volodymyr Zelenskiy has said Kyiv is ready to join such a ceasefire - discussed on Tuesday between U.S. President Donald Trump and Russian President Vladimir Putin - if there is a documented agreement with Russia.

Ukrainian officials have also accused Russia of breaking its word on the ceasefire by launching attacks on civilian targets. Zelenskiy said on Wednesday that Russian attacks on infrastructure, including hospitals and rail equipment, showed "Putin's words are very different from reality".

(Reporting by Reuters; Editing by Mark Trevelyan)