The document stemmed from a four-month investigation prompted by reports from a Mallorca newspaper on the arrivals of suspicious aircraft.

The newspaper, Diario de Mallorca, said a CIA plane that took off from the Mediterranean island was involved in the alleged kidnapping of a Lebanese-born German national, who says he was transported to Afghanistan, questioned as an al-Qaida suspect and tortured.

Bartomeu Barcelo, the chief prosecutor for the Balearic Islands, which include Mallorca, submitted the investigative report to the National Court in July, court officials said. They spoke on condition of anonymity because court rules bar them from giving their names.

Diario de Mallorca also reported this month that Spanish police have identified three planes — a Boeing 737 and two Gulfstream jets — as having been used by the CIA at the airport in Mallorca's capital, Palma, in its "extraordinary rendition" program.

The CIA declined to comment Monday on the reports.

The U.S. government has been criticized by human rights groups for practicing "extraordinary rendition" — sending suspected terrorists to foreign countries, where they are detained, interrogated and subjected to possible ill-treatment.

The prosecutor's office declined to comment on the report on Monday, as did police in Mallorca. The Spanish court officials said it was not clear if the National Court had begun to or agreed to undertake its own probe.

In a series of articles that began in March, Diario de Mallorca said more than a dozen CIA flights had used Palma airport. It said that in one case, a CIA plane involved in the alleged kidnapping of Khaled al-Masri in Macedonia early last year had taken off from Palma airport en route to the Balkan country.

Al-Masri says he was abducted, flown to Afghanistan and interrogated for suspected ties to al-Qaida.

Weeks later, al-Masri has said, he was turned over to officials he believes were from the United States who flew him to a prison in Afghanistan — where he claims he was shackled, beaten, injected with drugs and questioned persistently about his alleged links with al-Qaida.

He says he staged a hunger strike and was released in May this year after being flown to Albania.

Italy and Germany also are investigating alleged CIA involvement in the kidnapping of an alleged Muslim extremist.

Italian prosecutors are seeking the extradition of 22 purported CIA operatives accused of kidnapping an Egyptian cleric, Osama Moustafa Hassan Nasr, in 2003 in Milan.

German prosecutors are investigating the same case on grounds that one of the CIA agents may have touched German soil when the plane carrying the suspect to Egypt passed through Ramstein Air Base. The base is considered U.S. territory. Nasr was allegedly tortured in Egypt.