Food, medical supplies and vehicles were taken by the rebels, who were believed en route to the major town of Bambari.
The Ndassima camp was effectively shut down for the Christmas break and only minimal staff and security were on duty.
"The occupation occurred without violence and the Axmin staff are all accounted for and are in good health," the company said in a statement Monday.
"Whilst I deeply regret this event, I am relieved that all personnel are safe and that there were no injuries during this temporary occupation," said president and CEO George Roach said.
"We remain in close contact in the CAR (Central African Republic) and will report any significant developments," Roach said, adding that the company's 2006 mining convention and 2010 addendum provide full protection "both under circumstances such as this and more particularly in the event there is any change in overall administration in the CAR."
Axmin is a Canadian exploration and development company with a strong focus on central and West Africa, including the Central African Republic, Mozambique and Senegal.
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