Ukraine’s navy said Thursday it destroyed a large Russian landing ship in the southern port of Berdyansk, which has been occupied by Russia for weeks. Russia has been using the port, on the Sea of Azoz about 50 miles east of besieged Mariupol, to deliver military and other supplies to its invasion force. 

“The damage to the ship was captured in social media videos verified by The Washington Post and satellite images,” the Post repots. “The flames were visible at far distances in clear skies and the smoke so dense that it appeared in images taken in space.” Ukraine said the destroyed ship was either the Orsk or the similar landing ship Saratov, and two smaller ships were captured on camera fleeing the port after the explosions. 

Russian officials didn’t immediately confirm the attack, but the Pentagon assesses that Ukraine did conduct a successful attack against Russian ships in Berdyansk, CNN reports. And Britain’s Ministry of Defense said Thursday that “Ukrainian forces have launched strikes against high value targets in Russian-occupied areas of Ukraine, including a landing ship and ammunition storage depots at Berdyansk.” 

Ukraine will portably “continue to target logistical assets in Russian-held areas,” forcing Russia to “prioritize the defense of their supply chain,” reducing “Russia’s ability to conduct offensive operations, and further damage already dwindling moral,” Britain’s Ministry of Defense added. 

There was disagreement on how important the attack was for Ukraine’s war effort.

“It’s a highlight for Ukrainians, particularly in the naval sphere, but it’s probably not significant for Russia,” independent defense analyst H.I. Sutton tells the Post. “It’s a setback, but it doesn’t change the strategic picture at all.” Andrii Ryzhenko, a former Ukrainian Navy captain now with the Kyiv think tank Center for Defense Strategies, told The Wall Street Journal that for Russia, these landing ships are “the easiest way to bring and feed their contingent,” and “our specialists say that at least for a few weeks, Berdyansk is closed for them for resupply because of damage to the port.”

Ryzhenko said he thought Ukraine used its Tochka-U ballistic missiles to hit the ships, but Ukrainian Defense Ministry spokesman Oleksandr Motuzyanyk said Thursday that the “tools” used were “not that important,” but “we can tell you for sure this operation has been a success.” You can watch the entire attack unfold below.