Ali Reza Asgari, a retired general who served in Iran's Revolutionary Guard, disappeared while on a private trip to Turkey in December 2006. In March of this year, a former German Defense Ministry official said Asgari had defected and was providing considerable information to the West on Iran's nuclear program.
Iranian officials and Asgari's family have claimed that he was abducted.
One of Sunday's Web reports, on a site called Alef, said German and British intelligence services assisted Israeli agents in abducting Asgari and taking him to Israel. The site, http://www.alef.ir, is close to a conservative Iranian lawmaker.
"On the basis of a two-year investigation carried out by concerned bodies, Asgari was abducted by foreign intelligence services and is being held in a Zionist prison," the site reported, apparently referring to an Iranian intelligence probe into the matter.
"Asgari was abducted with the cooperation of Mossad as well as German and British intelligence services and was finally taken to Israel," the news report said.
Israel's Foreign Ministry refused to comment.
Hans Ruehle, a former chief of the planning staff of the German Defense Ministry, wrote in a Swiss newspaper in March that Asgari told the West that Iran was financing North Korean steps to transform Syria into a nuclear weapons power, leading to an Israeli airstrike that targeted a site in Syria on Sept. 6, 2007.
The U.S. claims the site was a nearly finished nuclear reactor, but Syria denies that and says the facility was an unused military installation.
Ruehle said Asgari, who was instrumental in establishing the Hezbollah militant group in Lebanon, "changed sides" and provided information to the West on Iran's own nuclear program.
The U.S. and its European allies, as well as Israel, suspect Iran is intent on using a civilian nuclear program as a cover for developing nuclear weapons. Iran denies that and says it only wants to generate power.
Iranian officials have said Asgari was not linked to Iran's nuclear program, but Western media reports have said he has cooperated with U.S. intelligence and is considered a "high value" defector.
Asgari, who became involved in the olive business after retirement, arrived in Turkey on a private visit from Damascus, Syria, on Dec. 7, 2006, and disappeared on Dec. 9, according to Iranian officials.
Ziba Ahmadi, one of Asgari's two wives, claimed at the time that her husband did not defect to Turkey and she believed "some evidence" showed he was abducted.