UKRAINIAN forces claim to have shot dead the deputy commander of Russia's Black Sea Fleet in another damaging blow to Vladimir Putin's forces. First rank captain Andrey Paliy, 51, is the first senior Russian naval official to be killed in the war with Ukraine so far.He was reportedly involved with Russian marine attacks near the port city of Mariupol when he died, although the exact circumstances of his reported death are not known. Moscow is yet to officially acknowledge his death, but it appeared to be confirmed by fellow Russian Konstantin Tsarenko, secretary of the public council at Sevastopol Nakhimov Naval School. Ukrainian official Anton Gerashchenko also claimed Paliy had been killed earlier on Sunday without giving any further details. Paliy was born in the Ukrainian capital Kyiv but refused to take a Ukrainian military oath in 1993, instead opting to serve in the Russian Northern Fleet.He had earlier served on the Russian nuclear missile cruiser "Peter the Great", and was deputy head of the Russian naval academy in Sevastopol, in the annexed territory of Crimea. It comes as Ukraine claimed to have killed a fifth Russian general, further damaging the resolve of Putin's army. Lieutenant-General Andrei Mordvichev, commander of the 8th Combined Arms Army, died in fighting at Chornobaivka, near the southern city of Kherson. Major-General Oleg Mityaev, 47, was killed in Mariupol on Wednesday, bringing the total number of Russian officers to die since the start of the war to 13.A picture of the corpse of the decorated military officer, a father-of-two, was released by Ukrainian Interior Ministry adviser Anton Gerashchenko. Lieutenant General Andrei Mordvichev - the commander of the 8th General Army - died during fighting on Friday night in a fresh blow to Vladimir Putin's invasion of Ukraine. It's thought the military boss was killed in the Russian-controlled Kherson Airport, which has been hit with Ukranian strikes in the past few days. A statement from the army general staff in Kyiv read: "As a result of fire on the enemy by the Armed Forces of Ukraine, the commander of the 8th All-Military Army of the Southern Military District of the Armed Forces of the Russian Federation, Lieutenant-General Andrey Mordvishev was killed." He is the latest top Russian military official to die in the war.Russia confirmed the death of Colonel Sergei Sukharev of the 331st Guards Parachute Assault Regiment on Friday. The elite paratroop commander died following fierce fighting near Hostomel. His death comes after that of a spy captain during a "top-secret" operation in Ukraine meaning Vladimir Putin has now lost a total of 13 commanders in the invasion. GRU military intelligence spy Captain Alexey Glushchak, 31, from Tyumen in Siberia, died in the carnage in Mariupol but details of his death have not been released. "Due to the strict secrecy of the military operation, the circumstances of the death of the Tyumen hero are not disclosed," a statement read. The GRU was behind the poisoning of defected spy Sergei Skripal with Novichok in Salisbury. Pictures emerged of father-of-one Glushchak’s funeral in Russia, where he was buried with full military honours and a guard of honour. On the day the military intelligence officer died he had spoken to both his wife and mother in Russia, it was revealed. He called to congratulate them on International Women’s Day but on the same day in the evening they learned he had been killed. His death coincides with the first expressions of anger and dismay on the number of coffins now returning to Russia, even though those officially acknowledged as having fallen in Ukraine are seen as a small fraction of the total number which best estimates suggest now run into many thousands. Glushchak will be posthumously decorated.A funeral was also held for Corporal Danil Novolodsky, 24, a senior gunner on an air assault artillery battery. He was awarded the Order of Courage under a decree signed by Vladimir Putin. Another funeral was held for Vladimir Plekhanov, 24, an orphan raised by a foster family. Sagyndyk Kudaibergenov, 22, from Tyumen, like the GRU agent, was buried with military honours, say reports. He was killed in mortar fire while deploying communications equipment across a river. Kudaibergenov was killed on February 26 but his funeral was only on March 11. It is reported that Russia is secretly transporting corpses of fallen Russian soldiers home at night on trains and ambulances via Belarus, to try and hide the true scale of the death toll. Around 7,000 Russian troops are thought to have died and up to 21,000 have been injured, according to US military sources. As Putin's forces face heavy losses, they have stepped up their indiscriminate attacks on civilian targets.On Sunday, Russia reportedly bombed a school in Mariupol where 400 were hiding from shelling. A number of women and children are said to be trapped under the rubble.