The crisis began earlier after Russia stopped the three Ukrainian ships from entering the Sea of Azov via the Kerch Strait by placing a cargo ship beneath a Russian-controlled bridge.

The Ukrainian navy said on social media that two Ukrainian sailors had been wounded in the subsequent seizure of its ships and that the alleged Russian attack on them had occurred after they had retreated and headed back towards Odessa, the Black Sea port from where they had begun their journey.

It also said in a Facebook post that two ships, Berdyansk and the Nicopol, were damaged.

The Ukrainian ships seized by Russia are being camouflaged….. Credit: @JulianRoepcke pic.twitter.com/eIDOPkGyGT — Henry Jones (@hthjones) November 26, 2018

“After leaving the 12-mile zone, the Russian Federation’s FSB opened fire at the flotilla belonging to… the armed forces of Ukraine,” the navy said, with officials from both countries accusing the other of provocative behaviour.

EXTRAORDINARY quote, allegedly from a Russian Navy commander: “We should assault them, we have to destroy them, f**k! Medvedev is in panic, it seems that the President is controlling all that sh*t” — Henry Jones (@hthjones) November 26, 2018

Later that day, Ukrainian Preisdent Poroshenko signed decree on martial law, and sent to the parliament for approval.

LATEST: Reports from @kgorchinskaya that there may not be enough MPs available to vote for martial law today – difficult to get to Kiev due to the weather (lots of snow). @eurocontrol reporting delays at Kiev’s airports — Henry Jones (@hthjones) November 26, 2018

Oleksandr Turchynov, Secretary of the National Security and Defence Council of Ukraine, has reportedly said that the incident was an act of war by Russia.

He has also stated that active military preparations have been spotted along the border on the Russian side.