He made the remarks in an exclusive interview with the Islamic Republic News Agency (IRNA) on the occasion of kidnapping anniversary of Imam Mussa Sadr.
Qasemi pointed to role and position of Imam Mussa Sadr in promoting and expanding co-existence lifestyle among Islam and other divine religions.
The spokesman said Foreign Ministry is following up the case constantly in different manners, while other groups and different tribes, Shia and non-Shia are trying to clarify the case.
Many believe that there is no evidence for death of Imam Mussa Sadr, he said, adding that following fall of Qaddafi regime in Libya both Islamic Republic of Iran as well as layers of his family are trying to find out the case.
Qasemi added that the case is following up in Lebanon, Italy and other countries through legal mechanism by his family's layers.
Imam Mussa Sadr arrived in Libya on August 25, 1979 at the invitation of former President Muammar Qaddafi and was kidnapped on August 31.
Evidence indicated that Imam Sadr might have been alive and maybe serving a life sentence.
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