JOHANNESBURG, South Africa (AP) — Zimbabwe’s President Robert Mugabe was in South Africa on Thursday as his wife faced accusations of assaulting a young model and police said a “red alert” had been issued to prevent her from leaving the country.

Mugabe, 94, flew into Waterkloof Air Force Base in Pretoria with his entourage late Wednesday night, apparently to help his wife with the scandal. He arrived early for a regional summit of southern African nations to be held this weekend.

South Africa’s Minister of Police Fikile Mbalula said all borders have been notified to prevent Grace Mugabe from leaving the country before the matter is resolved, according to the African News Agency.

“The SAPS (South Africa Police Service) have already put tabs in the borders in relation to her (Mugabe) leaving the country so there is no question about that. The red alert has been put,” Mbalula told reporters in Pretoria.

South African authorities are debating whether to grant Grace Mugabe, 52, diplomatic immunity, which Zimbabwe’s government has requested.

The model who accuses Zimbabwe’s first lady of assault, 20-year-old Gabriella Engels, has been offered legal assistance by a prominent lawyer who secured the murder conviction of Oscar Pistorius.

Engels registered a case with police on Monday accusing Grace Mugabe of attacking her with an extension cord in a luxury hotel in a Johannesburg suburb late Sunday evening.

Engels said she been in a hotel room with mutual friends of Mugabe’s two sons, who live in Johannesburg, when the first lady burst into the room and allegedly assaulted her. Photos of Engels posted on social media show a bloody gash to her forehead that she claimed was a result of the encounter.

Gerrie Nel, a former state prosecutor who now works as a private prosecutor for AfriForum, an organisation that primarily represents the rights of South Africa’s white Afrikaner minority, said he will offer help to Engels.

Nel told reporters that there was the “possibility of political interference” in the case. He said diplomatic immunity can’t be sued to “escape prosecution from grave crimes.”

South African police told local media they awaited instructions from the Department of International Relations and Cooperation on how to proceed. A department spokesman declined to comment on the status of Mugabe’s immunity bid on Thursday, but on Wednesday said the matter was under consideration.

It is unclear whether Grace Mugabe entered South Africa in a personal or an official capacity, which could impact her immunity appeal. Zimbabwe’s state-owned Herald newspaper reported last weekend that she was in South Africa seeking medical care.

The debate over whether Mugabe should be granted immunity quickly took on a political dimension in South Africa, with the opposition Democratic Alliance calling on the President Jacob Zuma’s cabinet to ensure Mugabe is brought to justice.

“Ms Mugabe should have applied for diplomatic immunity before she came to our country, not after she finds herself facing criminal charges,” the DA’s Zakhele Mbhele said in a statement.

The police minister “needs to do his job and ensure she is arrested and has her day in court to answer the serious charges against her.”