(CNN)An Iranian cargo ship sank in the Caspian Sea near Azerbaijan's Lankaran port on Friday, according to Iran's state-run news agency IRNA.
The Azerbaijan State Maritime Administration said it received a distress signal from an Iranian cargo ship near the port after it had been involved in an accident.
The crew of the Shabahang ship was pleading for help, saying, "we are sinking, we are sinking," according to IRNA reporting.
The Shabahang, which was carrying a shipment of tiles, was en route from Anzali port, in Iran, to Makhachkala, in Russia, when it crashed in an area about 23 miles from Astara port, in Azerbaijan.
After the crash, the Shabahang sank as water began to fill the ship, the Deputy Head of Iran Ports and Maritime Organization Jalil Eslami told IRNA.
Two Azerbaijan helicopters and the country's coast guard were involved in the rescue operation, resulting in the safe rescue of all nine crew members, who were still on board the vessel.
The crew consisted of seven Iranians and two Indians.
Full details on the cause of the accident are not yet clear.