The source said al-Qaida leader Ayman al-Zawahiri dispatched a veteran fighter to Libya in May to recruit fighters in the region near the Egyptian border.
He is believed to have mobilized some 200 people to join al-Qaida's efforts, CNN said Friday.
Western intelligence agencies have been concerned for some time about the potential for Islamist extremists to gain a foothold in Libya after the fall of former leader Moammar Gadhafi. CNN said militant groups have long been present in eastern Libya, although they were suppressed by Gadhafi's regime.
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