ANKARA, Turkey (AP) — A Guinea-Bissau flagged cargo ship with 14 crew members on board sank off Turkey’s Mediterranean coast on Wednesday, Turkish officials said. Five crew members were rescued while efforts to find nine others were underway.

The Joe 2 sank off the coast of Kumluca, in Antalya province, while heading to Ukraine from the Turkish port of Iskenderun, the state-run Anadolu Agency quoted Gov. Ersin Yazici as saying.

The cause of the ship sinking was not immediately clear.

The Turkish Coast Guard Command said it received a distress call at 3:47 a.m. and dispatched a vessel, several boats and two helicopters. Two crew members were rescued by the coast guard helicopters while three others were saved by other vessels in the area, it said.

All of the crew were Syrian nationals.

The coast guard said an investigation has been launched by the chief prosecutor’s office for Kumluca.