South Sudan's First Vice-President Riek Machar has been charged with murder, treason and crimes against humanity in a move that some fear could reignite the country's civil war.
Justice Minister Joseph Geng Akech said the charges against Machar relate to an attack in March by a militia allegedly linked to the vice-president.
The roads leading to his house in the capital, Juba, have been blocked by tanks and soldiers.
Forces loyal to Machar fought a five-year civil war against those backing President Salva Kiir until a 2018 peace deal ending the fighting in the world's newest country.
Machar has been under house arrest since March, with the UN, African Union and neighbouring countries all calling for calm.
