Seven Russian sailors and a Ukrainian have been kidnapped from a cargo ship in Nigerian waters, the Russian embassy in the West African nation said Wednesday.
The kidnappings come less than three months after three Russians were taken hostage off a ship in Nigerian waters and freed weeks later.
The Russian embassy posted messages on social media saying Nigerian authorities have been asked to help locate the victims. It did not give the day of the kidnapping, saying only that the men were taken off the BBC Caribbean, a cargo vessel owned by Dutch company Briese Shipping B.V. and flagged in Antigua and Barbuda.
Nigeria's navy and police refused to comment.
Ship hijackings and crew kidnappings are common off Nigeria's southern Atlantic coast. Hostages usually are released unharmed after a ransom is paid or crude from oil tankers is stolen.
Last year, the navy rescued several hostages in dangerous attacks on hijacked ships.
Also Wednesday, Nigeria's navy reported "another major feat" in rescuing two oil tankers attacked by pirates. A statement said its sailors saved the Mt Gaz Providence oil tanker on Tuesday, reacting to a distress call after the ship with a crew of 21 was attacked off southern Bonny Island.
The navy also said it twice repelled pirates trying to hijack the oil tanker Mt Rio Spirit after the vessel had loaded petroleum at ExxonMobil's Qua Iboe terminal, about 100 kilometers (60 miles) west of Bonny Island. The tanker was attacked even though it was escorted by a Navy vessel.
Associated Press writer Michelle Faul in Johannesburg contributed.