RFERL:

The son of the late Ayatollah Hossein Ali Montazeri has accused senior commanders of the Islamic Revolutionary Guards Corps (IRGC) of planting explosives in the luggage of unwitting Iranian Hajj pilgrims traveling to Mecca, Saudi Arabia in a failed 1986 terrorist plot.
Speaking to the privately produced but officially endorsed Khesht-e Kham internet TV show in late September, Ahmad Montazeri said his father told him six IRGC commanders who worked for then Parliament Speaker Akbar Hashemi Rafsanjani hid the explosives in the bags of up to 100 unsuspecting Hajj pilgrims. The plot was foiled by Saudi security forces, who found the explosives before any harm was done.
Rafsanjani, who was once considered one of the most powerful men in the Islamic Republic, died in January 2017 at age 82 under mysterious circumstances while swimming in a pool. His son, Mohsen Hashemi Rafsanjani, has called Montazeri’s accusation “irrational and immoral.”
Radio Farda's Hossein Ghavimi interviewed Montazeri, and asked him to explain his allegations. His father was heir to Khomeini in the 1980's but was pushed aside by other influential politicians, headed by Rafsanjani, who later engineered Ayatollah Ali Khamenei's appointment as Supreme Leader.

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