Russia's FSB released a video Tuesday of a detained Ukrainian naval officer claiming responsibility for an incident on the Black Sea which is pushing Ukraine and Russia toward the bring of war. The sailor, who appears to be reading form a script, says he provoked the Russian navy into firing on his ship.

A court in Russian-annexed Crimea ordered the first of 24 Ukrainian navy sailors captured by Russia to be detained for two months, the TASS news agency reported on Tuesday.

The sailors were detained on Sunday when Russia seized three Ukrainian vessels off the Crimean coast.

Russia accuses the sailors of illegally entering its territorial waters.

Read more: Russia vs. Ukraine: What's Behind the Black Sea Naval Standoff Pushing the Countries to Brink of War

Russia confirmed it was holding the sailors, who were detained in the Kerch Strait on Sunday, Interfax news agency cited Russian human rights commissioner Tatyana Moskalkova as saying on Monday.

She said three of the sailors were wounded in the incident and were recovering in hospital, but that they were not in a critical condition.

Russia seized two small Ukrainian armoured artillery vessels and a tug boat, which Moscow said had illegally entered Russia's territorial waters. Kiev said its vessels did nothing wrong and has accused Russia of military aggression. The incident led to Ukraine's President Petro Poroshenko to say there was now an "extremely serious" threat of a Russian land invasion.