Milan prosecutors on Saturday questioned an Italian intelligence chief in their probe into the alleged kidnapping of an Egyptian cleric by the CIA, Italian media reported.
SISMI director Nicolo Pollari was assisted by his lawyer during the questioning at the prosecutors' offices, the ANSA news agency said. SISMI is the military branch of Italy's intelligence services.
His lawyer could not immediately be reached for comment.
Pollari, who was questioned for the first time, is the highest-ranking official connected to the Italian investigation. Italian prosecutors have already issued arrest warrants for 26 Americans believed to have been involved in the abduction, reports CBS News correspondent Sabina Castelfranco.
Pollari has told European lawmakers that Italian agents played no role in the abduction and had no knowledge of it.
Earlier this month, the anti-terrorism prosecutors announced they had arrested two Italian intelligence officers, including one of Pollari's aides, as part of their investigation into the 2003 abduction on the cleric, Osama Moustafa Hassan Nasr.
The arrests of the two SISMI officials fueled allegations that Italy was among the European countries which allegedly aided the secret transfer of terror suspects to detention centers around the world.
Nasr, a terrorist suspect also known as Abu Omar, was taken by the CIA to the joint U.S.-Italian Aviano air base, flown to Germany and then to Egypt, according to prosecutors. Nasr, through his lawyer, has claimed he was tortured in Egypt.
Italy's new, center-left government has said that Italian intelligence services have denied any part in the abduction, which occurred when conservative leader Silvio Berlusconi, a staunch U.S. ally, was premier. Berlusconi has maintained that his government and the Italian secret services were not informed about, or involved in, the operation.
Prosecutors are seeking at least 25 Americans they say were CIA agents as well as an American who worked at Aviano.
The Berlusconi government refused to forward the prosecutors' extradition request to Washington, but the prosecutors could ask the new government of Romano Prodi to do so.