JOHANNESBURG: The 12th wife of the King of Swaziland, a former Miss Teen beauty contestant, has been placed under house arrest after she was allegedly caught with her lover, the Justice Minister.

Mswati Nothando Dube, 22, and the married minister, Ndumiso Mamba, were reportedly discovered by police in what is thought to have been a ''sting'' operation at the Royal Villas hotel in a town near Mbabane, the kingdom's capital.

With King Mswati III, 42, away on a state visit to Taiwan, she has reportedly been placed under surveillance at her mother-in-law's home and Mr Mamba is in jail on the king's orders.

Political commentators said the alleged affair was ''common knowledge''. Royal sources have said the king's mother - who shares power with her son and is known as the Indlovukazi or Great She-Elephant - had sent a delegation to Mr Mamba's village to lay charges of ''trespassing into another man's home''. He is known to have been a close friend of the king as well as his Minister for Justice and Constitutional Affairs.

Miss Dube first caught the king's eye when she was 16 at the annual Reed Dance, when tens of thousands of topless Swazi virgins pay homage to the monarch. Inkhosikati LaDube, as she became known, bore him a daughter within a year and a son soon afterwards.

Lucky Lukhele, of the pressure group Swaziland Solidarity Network, predicted that, if the charges were proved, Mr Mamba would get the death sentence and Miss Dube would be banished.

Telegraph, London