Protesters gathered in a square in the Libyan capital after Friday prayers and marched in an effort to drive militias out of Tripoli peacefully, CNN reported, citing Libya's state-run al-Wataniya TV.
Witnesses said militia members opened fire on the protesters with what appeared to be an antiaircraft cannon mounted on a truck as they neared a militia headquarters in a southern area of the city.
Fifteen of the 45 injured were reported in critical condition after the attack.
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