The flagship of Russia's Black Sea fleet, the Moskva missile cruiser, was badly damaged when ammunition on board blew up, Interfax news agency quoted the defence ministry as saying on Thursday, Trend reports citing Reuters.
Interfax said all the crew had been evacuated. It cited the ministry as blaming the blast on a fire and said the cause was being investigated.
"As the result of a fire on the Moskva missile cruiser, ammunition detonated. The ship was seriously damaged," the Russian Defense Ministry said in a statement. "The crew was completely evacuated."
Russian news agencies said the Moskva, commissioned in 1983, was armed with 16 anti-ship "Vulkan" cruise missiles with a range of at least 700 km (440 miles). Interfax did not give more details of the incident.