As of press time, large-scale joint search and rescue operations by sea, land and air forces are still underway, and the specific cause of the accident awaits official investigation and confirmation.

According to a briefing from the Istanbul Governor's Office, the accident took place at around 03:00 local time on September 2, in the Sea of Marmara waters roughly 18 nautical miles south of the Silivri coast on the western outskirts of Istanbul. The water depth at the incident site ranges from approximately 800 to 900 meters.

Based on information from the Turkish Directorate General of Maritime Affairs (DGMA) and multiple sources, the key timeline of the accident is as follows:

• At around 03:15, the two vessels collided;
• At 03:26, the EPIRB (Emergency Position Indicating Radio Beacon) signal of the sunken ship was picked up by COSPAS-SARSAT, the international satellite search and rescue system;
• At 03:41, the master of the other involved vessel ALSU called the Vessel Traffic Service (VTS) to report a collision with an unidentified vessel at approximately 03:15.

Only 11 minutes after the collision, the general cargo ship TUGBERK IMAMOGLU sank entirely.

Abdulkadir Uraloğlu, Turkey's Minister of Transport and Infrastructure, later confirmed that the vessel sank "extremely fast", taking just 11 minutes from impact to full submergence. Such a sinking speed is extremely rare for a 90-meter-class general cargo ship, and to a large extent accounts for why the crew failed to effectively organize abandonment and evacuation.

Vessel Profiles

Sunken vessel: M/V TUGBERK IMAMOGLU This multi-purpose general cargo ship (dry bulk carrier) was built in May 1990, with a ship age of 36 years. It has an overall length of 89.98 meters (about 90 meters), a moulded breadth of 12.8 meters, and a deadweight tonnage of around 4,598 DWT. Owned by Istanbul-based İmamoğlu Denizcilik, it was sailing from İskenderun Port (Derun Steel Mill Port) to Karadeniz Ereğli Port on the Black Sea coast at the time of the accident, loaded with some 4,200 tons of coiled steel plates and reinforcing bars. The vessel had a complement of 10 crew members including the master, all Turkish nationals. Its last AIS signal was logged at 22:42 on September 1 with no further updates, and the ship foundered rapidly after the collision.

Colliding vessel: M/T ALSU This product/chemical tanker was built in May 2022 (some sources cite 2021), with a ship age of roughly 4 years. It measures 90.8 meters in overall length, 13 meters in moulded breadth, and has a deadweight tonnage of 3,338 DWT. Its owner is Özpulathane Deniz Taşımacılığı. The tanker was in ballast condition at the time of the accident, undertaking a voyage from Kocaeli to Aliağa Port in the Aegean Sea. Following the collision, preliminary inspections revealed no obvious damage to the vessel. It arrived at Aliağa Port on September 4 and is currently at anchor pending further instructions.

Shipowner's Statement Discloses Prior Radio Warning

After the accident, İmamoğlu Denizcilik, the shipowner of the sunken vessel, issued a written statement on September 2, revealing a critical detail: before the collision, the master of TUGBERK IMAMOGLU had established contact with ALSU via VHF radio and explicitly warned the counterpart that it was intruding into his vessel's navigation area.

source：Vessel Value Visualization

Key points of the statement:

• Fairway compliance: Based on preliminary data and navigation records, TUGBERK IMAMOGLU was proceeding normally within the designated lane of the Sea of Marmara Traffic Separation Scheme (TSS), in full compliance with the International Regulations for Preventing Collisions at Sea (COLREGs) throughout the voyage.
• Sound technical status: No technical defects affecting navigation or maneuverability existed prior to the accident. The annual class survey was completed on schedule, and all relevant class and statutory certificates remained valid.
• Prior radio warning: Before the collision, the master established radio communication with M/T ALSU, clearly notified the other party of its intrusion into the vessel's navigation area and issued a warning, yet the collision still occurred.
• Preliminary attribution: Based on initial findings, the company attributes the accident to the navigational operations of ALSU. However, it emphasized that this judgment is only based on preliminary observations, and the final liability determination shall be subject to the official investigation conclusion.
• EPIRB-activated SAR: Following the collision, the EPIRB on board TUGBERK IMAMOGLU was triggered automatically, prompting public authorities to launch search and rescue operations. The master of ALSU also reported the accident to relevant departments afterwards.

Notably, when contacting VTS at 03:41, the master of ALSU described the colliding vessel as "unidentified" — a statement that stands in clear contradiction to the shipowner's claim of "established radio communication between the two vessels before the collision". The discrepancy remains to be verified after official retrieval of VDR (Voyage Data Recorder) data and communication records.

Search and Rescue Operations Underway

Following the incident, the Turkish Coast Guard Command, the General Directorate of Maritime Safety (Kıyı Emniyeti Genel Müdürlüğü) and the Marmara Strait Command responded immediately, dispatching multiple search and rescue craft and helicopters to the scene.

Rescue personnel have located life-saving appliances from the sunken ship at the accident site, including its free-fall lifeboat. However, no trace of the crew has been found and no survivors have been recovered as of yet.

The Turkish Directorate General of Maritime Affairs stated in a release: "There are 10 crew members on board including the master, all Turkish citizens. What is confirmed is that the ship sank extremely quickly."