ZAGREB, Croatia (AP) — Croatian police on Friday brought in for questioning several people over the disappearance last October of a luxury yacht from an Adriatic Sea marina where it was held as part of Western sanctions imposed on oligarchs with links to Russian President Vladimir Putin.

The disappearance of the 35-meter Irina Vu from the marina on the island of Murter was only recently noticed and reported by local media. The yacht reportedly sailed to Turkey and another one was left in its place.

The incident has triggered public criticism of the authorities in Croatia. The luxury vessel was one of five impounded in the country because they belonged to Russia-linked tycoons who came under international sanctions following the Russian invasion of Ukraine.

The government has replaced officials in charge of coastal security and the Murter marina while also stepping up monitoring of the remaining yachts.

The state HRT television said the missing yacht is worth around 5 million euros ($5.44 million.) Local media have reported that it belongs to the family of Russian metals magnate Alisher Usmanov and is apparently formally registered to his wife.

Croatian police gave no details about the suspects or the investigation. The statement added that officers have been conducting searches in several locations, including the suspects’ homes.

Croatia is a popular yachting destination because of its stunning coastline and hundreds of islands. Local media have also questioned how the yacht could sail all the way to Turkey without being registered and checked along the way.