Rosneft Chief Executive Igor Sechin attends a session of the St. Petersburg International Economic Forum (SPIEF), Russia, June 2, 2017.
Rosneft Chief Executive Igor Sechin attends a session of the St. Petersburg International Economic Forum (SPIEF), Russia, June 2, 2017. Reuters / SERGEI KARPUKHIN

Spanish authorities detained a mega-yacht called "Crescent" docked in the port of Tarragona in Catalonia, the Transport Ministry said on Wednesday, while a police source told Reuters the $600mln vessel was thought to belong to Igor Sechin, the sanctioned chief executive of Russian oil giant Rosneft.

The 135-metre-long yacht, described by specialist publications as one of the biggest in the world, sails under a Caiman Island flag and arrived in Spain from Italy in November 2021, according to monitoring site Marine Traffic.