A security official told United Press International the authorities are exerting every effort to find all those who took part in physically attacking Christophe Boltanski, reporter for the France's Libération daily.
Boltanski, 43, was beaten up Friday night near his hotel in Tunis, where he has been staying since Tuesday.
He said before returning to Paris Saturday he filed a police complaint against four unidentified men who assaulted him.
The journalist said one of the attackers sprayed pepper spray in his face to subdue him before he was stabbed with a knife and repeatedly beaten.
Tunisian Justice and Human Rights Minister Bashir Tekari told reporters the assault on Boltanski was a crime, but said such incidents can take place in any country.
He vowed the authorities will "hunt down everyone involved in this crime and bring them to justice."
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