An elite group of highly-trained dolphin soldiers, enlisted by the Ukrainian navy to detect submersible mines and combat invading vessels and troops, is now in the hands of Russian forces.

An employee at the Sevastopol oceanarium in Crimea, one of only two facilities in the world where dolphins are trained for military purposes, tells new agency RIA Novosti that the Russian Navy plans to preserve and redirect the animals for its own use.

"The oceanarium's engineers are developing new instruments for new applications to boost the operational efficiency of the dolphins underwater," said the source.

"Our experts have developed new devices, which convert the detection of objects by the dolphins' underwater sonar to a signal on an operator's monitor. But the Ukrainian Navy lacked the funds for such know-how, and some projects had to be shuttered."