Abdel-Razeq Nathouri was going from Benghazi to the base in the small eastern town of al-Marj, when the convoy was hit by an explosion some 20 km outside Benghazi.
Nathouri is chief of staff to forces run by Khalifa Haftar, the head of the Libyan National Army.
No further information has been provided yet, though AFP news agency said that the commander has managed to survive the assassination attempt.
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