Fugitive Croatian General Ante Gotovina is awaiting transfer to The Hague today after his arrest in Tenerife.
Gotovina spent the night in a Madrid jail but it was not clear when he would leave for the UN court, set up to prosecute war crimes committed as Yugoslavia disintegrated in the 1990s.
Spain's High Court yesterday ordered his immediate transfer to The Hague.
The arrest of the general, one of the three most wanted war crimes suspects from former Yugoslavia, is a major boost for the Hague tribunal.
His detention has brought calls for more efforts to catch Bosnian Serb wartime leader Radovan Karadzic and his military chief, Ratko Mladic.
Gotovina (50), is the last wanted war crimes suspect from Croatia and his arrest will ease Zagreb's path to joining the European Union.
He is charged with responsibility for the murders of at least 150 Serbs by troops under his command in the aftermath of the 1995 "Operation Storm", when Croatian forces retook parts of the country from Serb rebels.
Gotovina is also accused of pillage and destruction of their property. He has denied any wrongdoing and has been in hiding since his indictment in 2001.
Gotovina, carrying a false Croatian passport, was arrested while having dinner in a luxury hotel in the resort of Playa de las Americas.
Police in the Canary Islands started following Gotovina in September when they became suspicious about two people of Balkan origin travelling around the islands, staying in four-star hotels, never for more than a week at a time, Spanish newspaper El Mundoreported.
Authorities identified him by a guest registration form and a photocopy of his passport, newspapers said. He had been living on the islands for more than a year, Croatian newspaper Jutarnji Listreported.
He was arrested without force along with his bodyguard and identified himself. He was unarmed and was carrying €12,000, Spanish papers said.
Croatia long claimed Gotovina, an ex-Foreign Legionnaire, had fled abroad before his indictment was made public. He was later reportedly seen in Ireland, Italy, Bosnia and South Africa.