Tanker captain arrested over cargo ship sinking off Istanbul, prosecutors say

The captain of an oil tanker that collided with a cargo ship and sank off Istanbul leaving 10 crew missing has been arrested along with his third-in-command on charges of negligent homicide, prosecutors said on Friday.

The pair were arrested by a court late on Thursday, a day after the pre-dawn collision in which the ALSU, an empty oil tanker, struck the Tuğberk İmamoğlu, a cargo vessel carrying rolled steel, in the Sea of Marmara near Istanbul.

The case is being handled by prosecutors in Silivri on the western outskirts of Istanbul province.

According to the prosecutors' statement, the Silvri court charged the pair with negligent homicide for failing to fulfil their navigational safety obligations and take the necessary measures to prevent the collision.

It said the captain, identified only as A.E., "failed to fulfil his duty of supervision and oversight of navigational safety" while the other suspect, M.E., "who served as the third captain and watch officer at the time of the incident, failed to take the necessary measures to prevent the collision in a timely and effective manner."

The court ordered four other suspects be granted conditional release, it said.

Officials said the damaged cargo ship sank "very quickly" in waters about 900 metres deep, some 18 nautical miles (33 kilometres) off Silivri, leaving all 10 crew members missing.

Rescuers have yet to reach the wreckage of the Tuğberk İmamoğlu or locate its voyage data recorder (VDR) or "black box."

According to a marine accident expert report prepared for prosecutors, a copy of which was seen by the AFP news agency on Thursday, there were multiple breaches of safety procedures aboard the tanker.

"The fundamental root cause...resulting in a catastrophe, was the deficiencies and failures on the bridge of the M/T ALSU," it said.

It said an inexperienced third officer was at the helm and there was no lookout on duty, describing it as "serious negligence."

"No helmsman or lookout was posted on the bridge and the officer, who had only recently joined the vessel and lacked experience, was left alone on watch," the report said.

It also pointed to shortcomings on the part of the cargo ship.

Search and rescue operations continued on Friday.

Prosecutors have started legal proceedings against nine of the ALSU's 10 crew members, excluding the cook, six of whom appeared in court on Thursday.