A major maritime emergency unfolded in the Sea of Marmara off Istanbul, Türkiye, after two Turkish-flagged cargo vessels collided, leaving one vessel believed to have sunk within approximately 11 minutes and all 10 crew members on board missing.
The collision occurred at around 03:00 local time (00:00 GMT) on Wednesday, in the Marmara Sea, approximately 32 kilometres (20 miles) south of Silivri, according to authorities.
The vessel Tugberk İmamoglu, carrying 10 Turkish seafarers including its captain, lost contact following the collision with the Turkish-flagged Alsu. Authorities reported that the second vessel appeared to have suffered no significant damage.
Tugberk İmamoglu believed to have sunk rapidly
The 90-metre Tugberk İmamoglu was reportedly sailing from İskenderun, a major Mediterranean port in southern Türkiye, towards Eregli on the Black Sea coast.
Following the collision, communication with the vessel and its crew was lost. A lifeboat and other debris believed to belong to Tugberk İmamoglu were subsequently located.
Türkiye’s General Directorate of Maritime Affairs said the vessel was assessed to have sunk after it failed to respond to repeated calls and the mobile phones of personnel on board went unanswered.
Transport Minister Abdulkadir Uraloğlu said all 10 people aboard were Turkish nationals and included the vessel’s captain. Authorities estimated that the ship went down extremely quickly, in approximately 11 minutes after the collision.
At the time of the latest reports provided, no crew members had been found alive.
Second vessel remained afloat
The other vessel involved, the 91-metre Turkish-flagged Alsu, was reportedly travelling from Kocaeli, east of Istanbul, towards Aliağa on Türkiye’s Aegean coast.
Unlike Tugberk İmamoglu, Alsu remained afloat and was reported to be undamaged following the incident. The vessel remained anchored off Silivri while authorities continued their response.
Large-scale search and rescue operation
A major search and rescue operation was launched following the disappearance of the 10 crew members.
According to reports, the operation involved multiple Turkish agencies, including the Coast Guard, Navy, disaster management authorities and other emergency services.
The scale of the response included:
- 18 vessels
- 5 helicopters
- 2 drones
- 1 aircraft
- 1 naval vessel equipped for underwater search operations
Authorities continued searching the waters of the Marmara Sea for the missing seafarers, while debris and a lifeboat from the sunken vessel were recovered.
Collision in one of the world’s busiest maritime regions
The accident occurred in a strategically important area of Türkiye’s maritime network.
The Turkish Straits system, consisting of the Bosphorus and Dardanelles, with the Sea of Marmara between them, forms one of the world’s most important shipping corridors. The waterways provide a critical connection between the Mediterranean and Black Sea, with hundreds of thousands of vessel movements taking place through the wider Turkish Straits system each year.
The incident once again highlights the navigational and operational risks associated with high-density shipping routes, where commercial vessels operate in close proximity while transiting strategically important waters.
Investigation under way
Turkish authorities have begun an investigation into the circumstances surrounding the collision.
The immediate priority remains locating the 10 missing seafarers, while investigators will examine the circumstances leading to the collision, including the vessels’ movements, navigation, communications and other operational factors.
The rapid sinking of Tugberk İmamoglu — reportedly within approximately 11 minutes — has also become a critical element of the incident as authorities work to establish exactly what happened during and after the collision.