What is the legal status of a truce concluded by someone other than the Imam or his deputy?

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If a truce is concluded by anyone other than the Imam or his deputy, it is invalid (lam yasihh). However, if some individuals enter the abode of Islam under the presumed security of this invalid pact, they are granted temporary safety (aman) because they entered believing in security. They must then be returned to the abode of war (Dar al-Harb) and cannot remain in the abode of Islam, as the security pact itself was invalid.