How Instrumental Has The Mossad Been In Delaying Iran's Nuclear Program?

How instrumental has the Mossad (Institute for Intelligence and Special Operations) been in delaying Iran's nuclear program? According to recent media reports Israel's Mossad led by Meir Dagan may have succeeded in carrying out such attempts. Based on supposition rather than facts, the reports list a number of malfunctions that have occured in the past
year at different nuclear facilities in th More..e Islamic Republic. The disappearance of Ali Reza Asgari, an Iranian general in charge of his country's contacts with Hizbullah, an Iranian dealer of sophisticated communications systems who was charged with spying for Israel and sentenced to death.His sons were reportedly engineers who assisted in building Iranian centrifuges and were dubbed as double agents for the CIA. The mystery surrounding the death of Iranian nuclear physicist Ardeshire Hassanpopur in Feburary last year. At the time local Iranian media reports claimed he suffocated from fumes caused by a faulty gas fire. In the same month a mysterious explosion occurred at the nuclear research facility located at Tabriz.