The Latest: Zimbabwe blocks South African Airways flight

The Latest on assault allegations against Zimbabwe's first lady (all times local):

1:40 p.m.

A South African Airways flight bound for Johannesburg has been prevented from leaving Zimbabwe's capital, Harare.

Civil Aviation Authority of Zimbabwe chief executive David Chawota is not specifying the "issues" requiring attention before the plane is allowed to leave. He says "the South Africans know what should be done."

The cause of the delay is not clear. It comes as South Africa weighs Zimbabwe's request for diplomatic immunity for its first lady, who has been accused of assaulting a young model in Johannesburg.

South African Airways says in a statement it is awaiting a decision by Zimbabwean authorities. It says it is treating the matter as "urgent."


12: 30 p.m.

Zimbabwe's first lady is expected to make her first public appearance today since being accused of assaulting a young model at a luxury hotel in South Africa.

Local media are reporting that Grace Mugabe is expected to attend a regional summit Saturday with her husband in South Africa's capital, Pretoria. President Robert Mugabe is attending the Southern African Development Community's leaders' conference.

South African authorities are weighing a request by Zimbabwe's government for diplomatic immunity for the first lady, who has not commented.

Some demonstrators are protesting in Pretoria against the 93-year-old Mugabe and his wife, saying she should be prosecuted.

South African police have issued a "red alert" at the country's borders to ensure Grace Mugabe doesn't leave undetected, and are confident she remains in the country.