Tunis: According to the politician's attorney, a Tunisian investigative judge ordered Rached Ghannouchi, the leader of the Ennahda party and a well-known opponent of President Kais Saied, to be imprisoned on Thursday.

After an eight-hour investigation, the action against Ghannouchi, who was detained on Sunday, was taken on suspicion of plotting against internal state security, she added.

"It was a ready decision to imprison Ghannouchi only because Ghannouchi's expression of his opinion," attorney Monia Bouali told Reuters.

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After the judge's ruling, Ghannouchi posted a comment on his official Facebook page that read, "I am optimistic about the future."

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On Tuesday, the Salvation Front, the main opposition coalition, closed its headquarters and all offices of the opposition Ennahda Islamist party were prohibited from hosting meetings.

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The action, which comes a day after police detained Ghannouchi and three top officials, has Ennahda worried that it will lead to the party's eventual ban.