Fox said he suspected more than one person was attacked by the lions - based on the evidence found on the scene.
The handler heard a loud commotion coming from the lions but this is not uncommon, Mr Fox said.
"We thought they must have been rhino poachers but the axe confirmed it", Fox said.
Staff at Sibuya also found high powered hunting rifles with silencers, wire cutters and an axe used by poachers to cut off rhino horns. "But the lions are our watchers and guardians and they picked the wrong pride and became a meal".
At this point in the investigation, it's unclear how many poachers were killed by the lions.
Rhinoceros horn is a lucrative commodity on the black market, particularly in parts of Asia, where it is powdered and marketed to the rich as a cure-all medicine and legendary aphrodisiac. He added that "they were clearly intent on killing rhinos and cutting off their horns".
Nine rhinos were killed by poachers in Eastern Cape province, where the reserve is located, this year alone.
In 2016, the reserve lost three rhinos when poachers got into the park and shot them dead and cut off their horns. And South Africa is home to the most rhinos in the world - both the critically endangered black rhino and the near threatened white rhino - making them a target for poachers, who are often armed with guns and other equipment.
A vet was called to dart the entire pride of lions so that police forensic teams, assisted by the anti-poaching unit, could comb the immediate area for clues, Fox said.
Earlier this year lions killed and ate a poacher, leaving only his head and some remains.