Spokesman Reynold Thakhuli said no trace of the animal had been found in aerial and ground searches at the weekend.
“It has been particularly difficult to locate this animal due to the thickness of the bush…,” he said.
Rain and poor visibility prevented an aerial search on Monday morning, but it resumed in the afternoon. Thakhuli said it might be called off if the animal was not found by dark.
“Our suspicion is that it might have succumbed to the pain and died, and… if that is the case, we might start seeing vultures and other scavengers’ activities in the next two days or so.”
He asked anyone who saw the rhino to report the sighting at any gate or camp.
The rhino was seen near the Phabeni Gate on Friday by visitors, who alerted the authorities. A helicopter and rangers were sent to find the animal in the dense bush.
According to SanParks, 146 rhino have been poached in the country since the beginning of the year.