Correctional Services said that “matters are under control” at Johannesburg’s Sun City Prison on Wed.
The 38-year-old Sri Lanka offspinner will play the last Test of his career against India, starting July 18 in Galle.
Muralitharan has taken 792 wickets in 132 tests and 515 wickets in 337 one-day internationals. He is the world’s leading wicket-taker in both forms of the game.
The SLC said that Muralitharan had held talks with Sri Lanka selectors before making his decision, and had the blessing of the country’s President Mahinda Rajapakse.