The captain and third officer of oil tanker ALSU have been arrested on negligent homicide charges following a collision with cargo ship Tugberk Imamoglu in the Sea of Marmara.

Tugberk Imamoglu sank within 11 minutes of the collision and settled at a depth of 900 m. The vessel was carrying rolled steel, with the cargo weight reported to have accelerated the sinking. Ten crew members from the cargo ship remain missing as search and rescue operations continue.

Authorities in Silivri arrested nine of the 10 crew members aboard ALSU, excluding the cook. Six crew members later attended a court hearing on Thursday, and four were released under judicial supervision.

Prosecutors said the captain and third officer had not properly performed their duties before the accident. The captain was accused of failing to maintain navigational safety, while the third officer was serving as watch officer at the time of the collision.

According to the marine accident report prepared by officials handling the case in Silivri, the third officer did not have sufficient experience and was alone on watch. The report also identified several safety breaches aboard ALSU and shortcomings in the crew’s emergency response.

Prosecutors also cited the absence of a helmsman acting as lookout on the bridge as serious negligence. A preliminary investigation, however, also identified shortcomings in the operation of Tugberk Imamoglu.

The wreck of Tugberk Imamoglu was identified by Turkish Navy vessel TCG Akın. It remained unclear whether teams had reached the wreck to recover the ship’s data recorder for the investigation.