Ben Khalifa died while accompanying a militia patrolling the Qaser Bin Ghashir area south of Tripoli, according to Hamza Turkia, a freelance journalist.
The 35 year old photographer was also a freelance journalist who had contributed to the Associated Press news agency among other news organisations.
Condolences for his death came from around the journalism community in Libya, where he was known as one of its leading photographers.
A new round of fighting between rival militias erupted earlier this week, killing 13 people and wounding more than 50, according to the Libyan Health Ministry.
The clashes breach a shaky ceasefire brokered by the United Nations in September
Colleagues of Ben Khalifa cited his awards and exhibitions.
The fighting between militias allied with Libya's UN-backed government in Tripoli and an armed group from a nearby town underscores Libya's lingering lawlessness since the 2011 uprising that toppled and killed longtime leader Muammar Gaddafi.
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