TEHRAN, Iran—Iran on Thursday hanged two men convicted of trying to topple the country's clergy-led regime, the first known executions of opposition activists since unrest broke out following June's disputed presidential elections, the Web site of state television reported.

The report identified the two men as Mohammad Reza Ali Zamani and Arash Rahmanipour, and said they were convicted of trying to topple "the Islamic establishment" and of membership in armed opposition groups.

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