Ukraine says it has struck Russian naval targets and port infrastructure in the Crimean city of Sevastopol in what appears to be the biggest attack of the war on the home of the Russian navy's Black Sea Fleet.
A Ukrainian intelligence official said a large vessel and a submarine struck in the attack were so badly damaged as to be likely beyond repair.
The strike on Crimea, seized and annexed by Russia in 2014, was confirmed by officials in Moscow.
"We confirm a large landing vessel and submarine were hit. We do not comment on the means (used) for the strike," Ukrainian military intelligence official Andriy Yusov said, giving no further details on the scale of the damage.
Yusov later told a TV broadcast: "Those are significant damages. We can now say that with a high probability they are not subject to restoration."
Russia's defence ministry said in statement that Ukraine had attacked a Black Sea shipyard with 10 cruise missiles and three uncrewed speedboats in the early hours, damaging two military vessels that had been undergoing repairs.
It said it downed seven of the incoming missiles and that the attack boats had been destroyed by a Russian patrol ship.
Yuri Ihnat, spokesman for Ukraine's air force, was wary on the Russian assertion that its units had downed most of the incoming missiles.
"It's hard to say how many they were capable of downing," Ihnat told Ukrainian TV.
"It is important not to underestimate their anti-aircraft units. Perhaps they destroyed them. Perhaps not."
Retired Ukrainian navy captain Andriy Ryzhenko, speaking to Reuters by telephone, said: "It really is the biggest attack on Sevastopol since the beginning of the war."
The city is home to the Black Sea Fleet which the Kremlin uses to project power into the Middle East and Mediterranean and - during the war in Ukraine - to impose a de facto blockade on Ukraine's seaborne food exports via the Turkish straits.
Ukraine has tried to push back against the fleet's naval power by attacking with sea drones packed with explosives but Russia has continued to use its warships for missile attacks on Ukraine throughout the more than 18-month-old war.
It was not clear what kind of missile was used in the attack on Sevastopol, which lies about 300km from Ukraine's Black Sea port of Odesa.
Ryzhenko said Ukraine may have used domestically made Neptune anti-ship missiles that had been modified to work against ground targets.
United Kingdom-supplied Storm Shadow cruise missiles were another possibility, he said.
Sky News cited unnamed sources saying Storm Shadows were used in the attack.
The United States and European Union have poured weapons worth billions of dollars into Ukraine to help it fend off Russian forces that have occupied swathes of territory in the south and east since their full-scale invasion in February 2022.
The Ukrainian military, which launched a counteroffensive in early June, took the unusual step of publicly claiming responsibility for the strike, something it does not typically do for attacks on Russia or the Crimea peninsula.
"On the morning of September 13 the Ukrainian armed forces conducted successful strikes on naval assets and port infrastructure of the occupiers at the docks of temporarily occupied Sevastopol," it said on Telegram.
Mikhail Razvozhayev, the Russian-installed governor of Sevastopol, the largest city in Crimea and a major Black Sea port, said on Telegram that at least 24 people had been injured.
He posted a night photo of flames engulfing what appeared to be port infrastructure.
Russian Telegram channels posted videos and more photos of flames at a facility by the water.
On the streets of Sevastopol, residents said the attack had woken them up.
"My child was woken up as well. It was about 3 in the morning. We got very scared. Everything was shaking," said Nadezhda Lunyova.
