Two Italian spy chiefs were arrested today and a judge issued arrest warrants for four Americans over the alleged CIA kidnapping of a terrorism suspect in Milan in 2003, officials said.
Three of the Americans were alleged CIA agents and the fourth worked at a US military base in Aviano, northern Italy, from where prosecutors believe the Muslim cleric was secretly transferred out of Italy.
A statement from the Milan prosecutor's office said police arrested Marco Mancini, second in command at Italy's Sismi military intelligence agency, and were holding him in jail for his alleged role in the kidnap. Another Sismi official was placed under house arrest.
The suspects are accused of involvement in the 2003 abduction of Hassan Mustafa Osama Nasr, also known as Abu Omar. Prosecutors say a CIA-led team seized him on a Milan street in broad daylight, bundled him into a van and drove him to the Aviano air base.
He was then flown to Egypt where Nasr says he was tortured under questioning.
An Italian court has already issued arrest warrants for 22 suspected US agents over the abduction. But it was the first time Italian officials have been linked to the investigation.
If an Italian role is confirmed, it would add weight to allegations that European countries colluded with Washington in the secret "renditions", or transfers, of terrorism suspects.
The Rome government said in a statement that Italy's intelligence services had denied playing any role in the kidnapping and that it trusted their loyalty.
But some lawmakers in the new centre-left ruling coalition accused former Prime Minister Silvio Berlusconi of a cover-up during his five-year administration, which ended in April.
Mr Berlusconi, a close ally of US President George W. Bush, has fiercely denied his government or Sismi were involved in the kidnapping - and even once summoned the US ambassador over the matter to request Italian sovereignty be respected.