Pirates have attacked a Polish-owned cargo vessel off the Nigerian coast, kidnapping five crew members, Poland's authorities have confirmed.
Foreign Minister Witold Waszczykowski said on Friday that the captain, three officers and a sailor, all Polish citizens, were abducted on Thursday night from the Szafir, a Cyprus-registered ship en route from Antwerp to the Nigerian port of Onne.
A further 11 crew members, who escaped being taken by locking themselves inside the ship, were safe and in contact by phone, he added.
Waszczykowski said the as yet unidentified kidnappers have made no demands so far, and Poland was liaising with Nigerian authorities.
"The Polish ambassador [to Nigeria] is at the moment in the [Nigerian] foreign ministry, the relevant notes and letters to Nigerian authorities asking for support and help have been issued," he told a news conference.
"Now we are waiting for further developments."
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Asked if Poland will use its special forces to release the hostages, Waszczykowski said the matter is a responsibility for Nigeria.
"Those who have kidnapped our sailors have not formed requests yet. They usually demand a ransom or [have] political demands," he said.
"We will react depending on what demands are placed."
The ship is currently anchored about 56km off the Nigerian coast, with operator EuroAfrica arranging for a new crew to take it back to port, according to the Polish Maritime Minister Marek Grobarczyk.
"The captain and three officers are missing, so there is a problem in leading the ship to the safe port," he said.
"The ship's owner has brought pilots to the ship, who will safely lead the ship with the crew into the safe port."
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Security experts classify the waters off Nigeria as some of the deadliest on earth, with pirates based in the country often targeting oil tankers, as well as hostages to ransom.
But the region has seen no documented attacks since February, when a crude carrier was boarded with the ship's Greek deputy captain killed and three crew members taken hostage.