Six armed men have hijacked the product tanker Sibu 1 in the Gulf of Aden and diverted the vessel toward Somalia, according to the United Kingdom Maritime Trade Operations centre.

UKMTO received an initial incident report from a position about 136 nautical miles east of Al Mukalla, Yemen. The tanker, which was sailing west through the Gulf of Aden, transmitted a distress call on VHF Channel 16 after an unauthorised vessel approached it.

UKMTO subsequently reported that six armed individuals had boarded the tanker, taken control and redirected it toward Somalia. Authorities are investigating the incident, while ships operating nearby have been advised to exercise caution and report suspicious activity.

Maritime security sources identified the vessel as the 32,200-dwt Sibu 1, IMO number 9204776. Lloyd’s List also identified the tanker and reported that its Automatic Identification System broadcast the message “PIRATE ONBOARD HELP” before the vessel altered course.

MarineTraffic information cited in the report indicated that Sibu 1 changed its AIS destination to Port Sudan on August 15 and entered the Somalia High Risk Area at 1718 UTC on August 19. Its final reported position before the boarding showed the tanker proceeding west-southwest at approximately 9.3 knots.

Sibu 1 is subject to sanctions imposed by the US Treasury’s Office of Foreign Assets Control. Martin Kelly, head of advisory at EOS Risk Group, said United Against Nuclear Iran had also identified the vessel as part of Iran’s so-called ghost fleet.

OFAC sanctioned the tanker in December 2025, when it was named Seamull and managed by UAE-based Qatrat Alnada Almasi Ship Management. The US Treasury said at the time that the vessel had carried Iranian petroleum products, including naphtha and gasoil, on several occasions and had called at Houthi-controlled ports in Yemen.

The seizure follows the hijacking of the cargo ship Lutuf three days earlier. According to UKMTO, eight armed attackers boarded that vessel approximately four nautical miles south of Mareeyo, Somalia.

The incidents have raised concerns over renewed Somali piracy in the Gulf of Aden. A recent Joint Maritime Information Center assessment said southwest monsoon conditions were limiting long-range skiff operations offshore, although sheltered coastal waters continued to offer opportunities for pirate groups.

Other reported seizures this year include the product tanker Honour 25 and the general cargo ship Sward, both hijacked off Somalia in April amid the Strait of Hormuz crisis and renewed Houthi attacks on shipping.