Ukraine's military spy agency says a joint operation with a pro-Kyiv Russian group led to a Russian warship being set on fire in the Baltic Sea earlier this year.
A fire broke out on the Serpukhov missile ship, which was stationed in the Kaliningrad region, on 7 April.
The GUR military spy agency claimed responsibility shortly after.
In an update today, agency head Andriy Yusov said the operation was conducted in tandem with the Freedom of Russia Legion - a group of Russians opposed to Vladimir Putin's war in Ukraine.
