The city was rocked by a series of explosions early on Sunday morning.
Three thick columns of smoke and flames were then spotted in what is believed to be the city’s industrial area.
Anton Herashchenko, an adviser to Ukraine’s interior minister, said in a Telegram post that Odesa had been “attacked from the air” by missiles.
He claimed some of the missiles “were shot down by air defence.”
Odesa is a major port hub on the Black Sea and is a key strategic target for the Russian army.
It comes as the UK’s Ministry of Defence reported a concentration of Russian air activity in Ukraine’s south-east in its daily intelligence briefing.
While the Russians could still launch an amphibious landing, UK intelligence officials believe this would be extremely risky, given the time Ukrainian forces have had to prepare for such a scenario.
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