"Boljkovac was interviewed in the prosecutor's office this morning. He presented his defence and answered all the questions," lawyer Anto Nobilo told the press.

Boljkovac, who at the time served as chief of the Yugoslav secret police OZNA in Karlovac, is held responsible for an execution of 21 civilians at a site called Vidanka-Curak in May 1945 following the liberation of Duga Resa, about 70 kilometres southwest of Zagreb. Boljkovac later became Croatia's first interior minister after the country declared independence from Yugoslavia 20 years ago.

His son Matija Boljkovac told the media that several more witnesses, some from Croatia and some from Belgrade, would be heard in March. "I am confident that it will be over then and there will be no more investigations. I am not authorised to discuss any details of all this," he said.

Boljkovac was arrested last November and remanded in custody. Because of his advanced age and poor health, he spent most of his time in detention in a prison hospital. Less than a month later, the Constitutional Court quashed the rulings by the Zagreb County Court, saying that the procedure should be conducted in accordance with the new Criminal Procedure Act and that the investigation should be conducted by state prosecutors rather than by an investigating judge.

The State Prosecutor's Office has reopened the investigation but has not ordered the suspect's detention, so that Boljkovac will remain at large pending completion of the investigation.

Boljkovac has denied any wrongdoing.