A major search and rescue operation is continuing in the Sea of Marmara after the Turkish-flagged general cargo vessel M/V Tuğberk İmamoğlu sank following a collision with the Turkish-flagged tanker M/T ALSU in the early hours of 2 September 2026.
The collision occurred at approximately 03:15 local time, around 18 nautical miles south of Silivri, Istanbul.
Tuğberk İmamoğlu was sailing from Iskenderun towards Karadeniz Ereğli carrying rolled steel and steel products, while ALSU was travelling from Kocaeli to Aliağa and was reported to be empty at the time of the accident.
There were 10 Turkish crew members aboard Tuğberk İmamoğlu, including the vessel’s master. As of the latest information available on 2 September, none of the crew had been located.
Emergency signal received minutes after collision
One of the key elements emerging from the accident is the timeline immediately following the collision.
At 03:26, approximately 11 minutes after the reported impact, Türkiye’s COSPAS-SARSAT system received an emergency signal from Tuğberk İmamoğlu’s EPIRB.
Following receipt of the emergency beacon signal, attempts were made to contact the vessel by radio and to reach crew members using their registered mobile phone numbers, but no response was received.
Turkish authorities have indicated that the timing suggests Tuğberk İmamoğlu sank extremely rapidly following the collision.
At approximately 03:41, the master of ALSU contacted Vessel Traffic Services and reported that the tanker had been involved in a collision at around 03:15.
This places approximately 26 minutes between the reported time of the collision and ALSU’s notification to Vessel Traffic Services.
The circumstances surrounding that period are expected to form part of the official investigation.
Large-scale search and rescue operation
A major search operation was launched involving the Turkish Coast Guard, the Directorate General of Coastal Safety and other public authorities, with Turkish naval assets also deployed to support the effort.
Maritime and aerial units have been searching the accident area, where lifesaving equipment and debris believed to belong to Tuğberk İmamoğlu have been recovered.
An empty lifeboat and lifebuoys were among the items located on the sea surface.
The vessel is believed to have sunk in an area where the water depth is approximately 800 to 900 metres, presenting a significant challenge for any subsequent underwater investigation or recovery operation.
Search and rescue efforts for the 10 missing seafarers were continuing at the time of publication.
Vessel operator issues statement
Following the accident, İmamoğlu Denizcilik issued a statement saying that Tuğberk İmamoğlu had no known technical failure affecting its navigation or manoeuvrability before the collision and that its statutory and classification certificates were valid.
The company also stated that the master of Tuğberk İmamoğlu had established VHF communication with ALSU before the collision and had warned the tanker regarding its manoeuvre.
Turkish media have subsequently published what have been described as recordings of VHF communications between the two vessels shortly before the accident.
However, neither these recordings nor statements issued by the parties involved establish responsibility for the collision.
Investigation opened
The Silivri Public Prosecutor’s Office has opened a formal investigation into the accident.
Navigation data, radar records, VHF communications, vessel documentation and other available evidence are expected to be examined by maritime experts in order to reconstruct the movements of both vessels and determine the precise circumstances leading to the collision.
At this stage, the cause of the accident and the respective responsibility of the vessels have not been officially established.
The confirmed chronology currently places the collision at approximately 03:15, the activation of Tuğberk İmamoğlu’s EPIRB at 03:26 and ALSU’s report to Vessel Traffic Services at around 03:41.
Tuğberk İmamoğlu remains sunk in deep water while the search for all 10 missing crew members continues.
