(CNN)Zimbabwe's first lady Grace Mugabe is seeking diplomatic immunity over allegations of assault in South Africa.
Mugabe was supposed to present herself at a police station in a Johannesburg suburb on Tuesday to give a statement but failed to appear, despite her appointment being rescheduled several times throughout the day, South African police said.
Mugabe's attorneys informed authorities that she had "changed her mind" about speaking to police and subsequently requested diplomatic immunity, according to a police statement.
The alleged assault took place Sunday at a hotel in Sandton, a wealthy suburb north of Johannesburg, according to police, who were called to the scene where a case of "assault with intent to do grievous bodily harm" was registered.
The move comes after Gabriella Engels, a 20-year-old woman, used her personal Twitter feed to accuse Mugabe of attacking her, according to Vishnu Naidoo, a spokesman for South Africa's police.
Engels said she was in a hotel room with Mugabe's two adult sons when the attack took place.
"I had no clue who this woman was when she started beating me," Engels said in a radio interview with CapeTalk 567AM. "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."
Engels also claimed on Twitter that Mugabe "split my head open in 3 places. With an extension cord and plug to hit me."
CNN has reached out to Mugabe's representatives for comment.
Police initially claimed Mugabe had turned herself before revealing that she had not. Her attorneys and representatives of the Zimbabwean government met police on Tuesday to establish "channels of cooperation," police said.
The wife of Zimbabwean President Robert Mugabe, who has governed the country since 1980, is reportedly in South Africa to have a foot injury examined and to take part in diplomatic meetings.