The first images of one of Russia's most prestigious warships shortly before it sank are being shared online.
Ukraine says it struck the Moskva in a missile attack.
However, Russia says the damage to the flagship vessel was caused by a fire which detonated ammunition on board. It says the warship then sank during a storm.
Now, a short video and two images, uploaded by an unknown source or sources, appear to show the Moskva being escorted after sustaining damage. These images cast doubt on some of Russia's statements.
What do the images show?
This is the clearest image we have of the warship.
It has been identified by numerous naval experts as the flagship Moskva.
You can compare the ship in the photo with this image of the Moskva taken last year in Istanbul, with areas that match highlighted.
The archive photo also helps show how far the Moskva has begun to sink. The yellow line shows how high the waterline is in the recent photo being shared online.
This indicates the damaged Moskva has lost some buoyancy.
The new image also shows the damaged ship is noticeably leaning portside and towards the camera, whereas the archive photo shows the warship is sitting flat on the water.
Looking further at the image of the damaged warship, we can see a large crack in the side of the Moskva and what appears to be fire damage.
Infrastructure on the deck appears flattened and warped in places. Here is a direct comparison.
The Russian warship also seems to still be on fire in the image.
Analyst Oliver Alexander is one of a number of experts who highlight that the warship's rescue boats may have been deployed.
This indicates that those on board the warship had enough time to disembark the sinking ship using the lifeboats.
This supports the Russian Defence Ministry's statement that the crew were evacuated from the Moskva. However the image cannot tell us how many crew members may have escaped.
Defence analyst H I Sutton shared this graphic labelling the different parts of the warship and highlighting the main areas of damage.
Writing on his website, Mr Sutton says the limited evidence in the photos casts some doubt on Russia's claim a fire broke out, compared to Ukraine's claim that it struck the ship with missiles.
He writes: "The damage does not rule out a missile strike(s), and it remains the likely cause. Possible puncture marks in the side of the hull are visible below where the fire is.
"But these would need closer examination to confirm whether they were caused by missiles, or are simply fire damage."
A second image being shared online is much lower resolution and much of the vessel is hidden by smoke.
Some of the key markings and infrastructure of the warship are visible, helping confirm it is also an image of the Moskva.
What can a two-second video tell us?
A short video clip began to circulate around the same time as the photos.
Sky News has removed the audio from the video, as a man can be heard shouting in Russian: "Motherf*****! What the f*** are you doing?" before the camera moves down and then turns off.
The video shows the weather was fairly settled when the clip was filmed. Some wind can be heard in the original audio but the sea is calm and no rain can be seen.
This contradicts a statement put out by the Russian Defence Ministry that the ship sank during a storm.
A news report from Russian agency TASS on 14 April said: "The Moskva missile cruiser sank while being towed amid storm because of hull damage sustained during the detonation of ammunition, Russian Defence Ministry said Thursday."
Where do the images and video come from?
It is not known who took the images or videos, or why there was a delay in them coming to light.
The ship sank on Thursday while being towed to the Crimean port of Sevastopol, according to the Russian Defence Ministry in a statement to the country's news agency TASS.
However, the video and images only began to appear online on Sunday evening.
A naval expert who uses the handle @GrangerE04117 on Twitter offers insight into why there was a delay in the images and videos appearing online.
He told Sky News: "It took this long for images and videos to emerge because the crews of the tugboats probably recently returned to the home base in Sevastopol.
"Or if they did return immediately after the ship sank... the crew probably contemplated releasing videos of the ship immediately and just waited a few days."
The person who filmed and photographed the Moskva is unknown, but Yoruk Isik, an open source analyst with years of experience tracking ships, believes the photo may have been taken from a Russian rescue ship.
The video clip has been going viral on Russian social media. A watermark for a group with four million subscribers called молния (Lightening) on messaging app Viber can be seen on the two-second clip.
This information suggests it may have been a Russian person who captured the last images of Russia's flagship missile cruiser.
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