The captain of the 5,100-dwt Kanton (built 2006) was also held, the Moscow Times reported, citing prosecutors in Ukraine, which controlled the Crimean peninsula until last year.

The Tuvalu-flagged vessel is in the port of Kherson.

Prosecutors said the crew could be jailed or up to three years and the vessel seized.

Ukraine has said any visit to Crimean ports is illegal and a ban came into effect in July last year.

But