Russian officials prevented an attack plot after discovering a naval mine mounted on the hull of the Arrhenius liquefied petroleum gas (LPG) tanker from Belgium.
According to a statement from the Russian Investigative Committee on May 25, naval mines manufactured in a NATO member country were discovered by divers during the inspection of the Arrhenius hull.
All naval mines have been safely removed and tested within the framework of criminal investigation. According to the Russian Investigation Committee, the explosives are "naval magnetic naval mines, believed to be manufactured in a NATO country using industrial production components".
Russian Investigative Committee spokeswoman Svetlana Petrenko emphasized that these naval mines were produced in a NATO country.
Based on initial investigations, it can be concluded that these magnetic naval mines cannot be attached to ships in Russian territorial waters," spokesman Petrenko said.
However, TASS news agency quoted an opinion that this may be a self-made hull-mounted mine, instead of a NATO military model that can be clearly identified.
Russian media reported that 2 naval mines were located near the engine room area, each containing about 7kg of explosives.
Meanwhile, a NATO official affirmed that the alliance did not plant naval mines on any oil tankers.
The Arrhenius ship just docked at Ust-Luga port in the Baltic Sea after a voyage from Antwerp port of Belgium. According to ship tracking data, the Arrhenius ship has a tonnage of about 26,645 tons, is flying the flag of Liberia and is managed by Maple Mariner Holding Company headquartered in the United Arab Emirates. The Arrhenius ship docked at Ust-Luga port on May 20 and is expected to depart for Samsun port in Turkey afterwards.
Captain Arrhenius of the ship testified to officials that after liquefied natural gas, the ship moved to Antwerp, but when it arrived on May 12, it had to anchor offshore because the port was not ready to receive it. The strike of port workers in Belgium is believed to be the cause of this delay. The ship had to wait about 36 hours to dock and took about 25 more hours to unload goods. After leaving Antwerp on May 16, the ship went straight to Ust-Luga without stopping anywhere else.
The crew was evacuated from the ship to handle the mines, but then the sailors were allowed to return to work. Currently, the ship is still anchored outside the Ust-Luga area and is expected to receive cargo before continuing its journey to Turkey.
Russia has strengthened security measures at seaports after suspected sabotage targeting the country's energy infrastructure. Last year, Russia asked divers to inspect the hull at seaports after attacks targeting 4 oil tankers. Previously, the large oil tanker Koala was trapped at Ust-Luga after an explosion in the engine room in February 2025.
