Pretoria - Police Minister Fikile Mbalula on Thursday said that police have put out a "red alert" at South African borders for Zimbabwean first lady Grace Mugabe, in case she attempted to leave the country.Speaking at the sidelines of an indaba on gender based violence, Mbalula said security measures have been put at the borders, however, she had not made any attempts to leave. Matters involving her diplomatic immunity still needed to be resolved."We, in terms of South African Police, already put tabs in the borders in relation to her leaving the country, so there is no question about that," said Mbalula."So tabs have been put, a red alert has been put, so she is not somebody who has been running away," he said.Mugabe has been accused of assaulting South African model Gabriella Engels at a Sandton hotel last weekend. She was visiting her sons on Sunday when she reportedly stormed into their room and assaulted Engels, who she accused of living with her sons - who are both in their 20s and live in Johannesburg.Mugabe allegedly assaulted Engels with an electric cord in the face and head. The model sustained serious injuries and has since laid a charge of assault with the intent to do grievous bodily harm.The police ministry had previously announced that Mugabe would be appearing in court to answer for the charges but she never pitched.It was also reported that she would hand herself over to police to give a warning statement, this also never happened.In a subsequent press release the ministry said her lawyers and government representatives made verbal representations to SAPS investigators that the suspect wished to invoke diplomatic immunity cover and she elected to change her mind about the warning statement.'Nothing will just be left'Mbalula said since the matter was now in the hands of Dirco."There has been an exchange since the day I announced she would appear in the Wynberg Magistrate's Court, which was an agreement, she didn't appear up until the point now, where issues of immunity must be attended to."Mbalula added that, had it been someone else facing such allegations, they could have already moved on the person in terms of the issues."Anyone that comes to South Africa must know we are a constitutional state and a law state and nothing will just be left."It has been reported that President Robert Mugabe has arrived in South Africa two days early for the 37th SADC Heads of State and Government Summit.