Iran state TV says 13 killed in Tehran clashes

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TEHRAN, June 21 (Reuters) - Iranian state television said 13 people had been killed in clashes between police and "terrorist groups" in Tehran, in an apparent reference to street unrest in the capital on Saturday.

Iran's English-language Press TV also said "rioters" had set two gas stations on fire and attacked a military post.

"Thirteen people killed in police clashes with terrorist groups in Tehran," it said in a headline.

State television earlier said Iran's Intelligence Ministry had arrested members of an exiled opposition group it acccused of "terrorist activities" including setting buses on fire and destroying public property. (Reporting by Zahra Hosseinian; Writing by Fredrik Dahl; Editing by Louise Ireland)