Vishnu Naidoo, a spokesman for South Africa's police, told CNN that Gabriella Engels used her personal Twitter feed
to accuse Mugabe of attacking her.
Engels tweeted that Mugabe "split my head open in 3 places. With an extension cord and plug to hit me."
Engels said she was in a hotel room with Mugabe's two adult sons when the attack took place.
In a radio interview with CapeTalk 567AM
, Engels said: "I don't really want to go into details as to what happened at the hotel because I'm scared it might jeopardize my case."
Engels also said she was not friendly with the Mugabe sons, adding that she met them for the first time on Sunday before the alleged assault.
"I had no clue who this woman was when she started beating me," Engels said. "I only found out this after I came out the hotel room. "I walked by a security guard and asked him who the woman was because I wanted to lay a case against her."
CNN has reached out to Mugabe's representatives for comment.
According to South African police, the alleged assault took place Sunday at a hotel in Sandton, a wealthy suburb north of Johannesburg.
Police say they were called to the scene where a case of "assault with intent to do grievous bodily harm" was registered.
There was confusion surrounding Mugabe's whereabouts on Tuesday, with police first claiming she had turned herself in before revealing that she had not.
"The suspect was supposed to hand herself in but that did not materialize," Naidoo said.
Naidoo did not name Mugabe directly but referred to a "prominent woman" who would not be identified until she appears in court.
"We are not at a point that we must arrest a suspect," Naidoo added. "We must finalize our investigations and take it to the senior public prosecutor, and we haven't reached that point."
Mugabe, 52, was reportedly in the country to have an injury to her foot examined.