Grace Mugabe returned to Zimbabwe early on Sunday, state media reported, after a 20-year-old model accused the first lady of assaulting her in an upmarket Johannesburg hotel room.
South Africa granted Grace Mugabe diplomatic immunity, a security source told Reuters on Friday.
Zimbabwean state media reported that President Robert Mugabe and the first lady arrived in Harare aboard an Air Zimbabwe plane. A source confirmed this to Reuters.
Harare has made no official comment on the allegations and requests for comment from Zimbabwean government officials have gone unanswered.
The South African government has restricted all official comment to the police ministry.