Berlin - Germany handed nine pirates, captured off Somalia, to Kenyan custody on Tuesday, where the men now face prosecution for attacking a merchant vessel in the Gulf of Aden.

The German foreign ministry confirmed that the Kenyan police received the marauders in the harbour city of Mombasa, where the navy frigate Rheinland Pfalz had docked a week after seizing the nine men.

The frigate, which forms part of the EU's anti-piracy mission Atalanta, had apprehended the pirates when they attacked a German merchant vessel with anti-tank missiles and firearms.

Tuesday's handover was only possible after a hastily signed agreement between the European Union and Kenya paved the way for the Somalis to be prosecuted in the neighbouring state.

Somalia, where the majority of pirates operating in the Gulf of Eden originate, lacks a functioning legal infrastucture in which to try the men.

German prosecutors had also washed their hands of the captives, stating that national interests had not been sufficiently at stake to put them on trial in Germany.

The German-owned merchant vessel was sailing under an Antiguan flag, and none of the crew was German.

The Kenyan justice system meets the minimum standards required by Germany, although human rights experts are critical of conditions in the country's courts and jails.

Human Rights Watch expressed criticism when the US government agreed a procedure to hand captured pirates to Kenya, saying inmates could be held for months without charge, were often denied legal advice and that trials could be put on hold for months.

The details of the agreement struck with the EU specifies that the pirates can't be tortured or sentenced to death, stipulates that they should appear imminently before a judge and entitles them to a lawyer and an interpreter. (dpa)