"Pirates seized a small Dutch ship with eight crew. It was hijacked in the Gulf of Aden two hours ago (around 0730 GMT)," said the head of the programme, Andrew Mwangura.
No more information on the type of ship or its owners was immediately available, Mwangura said.
The latest hijacking brought to at least 20 the number of ships currently held by pirates in the Gulf of Aden and Indian Ocean, together with more than 300 seamen.
On Wednesday, pirates released an Emirati-owned cargo they had captured five days earlier after confirming that it had been chartered by Somali traders.
But they also hijacked a German cargo, the MV Victoria, and its 11 Romanian crew despite the vessel registering its journey with the European Union's anti-piracy naval mission Atalanta and sailing inside the internationally-recommended transit corridor.