Former South African president Jacob Zuma has been moved to hospital to undergo surgery and remains in hospital with more operations planned according to prison authorities.

Zuma, who is serving a 15-month sentence in Estcourt prison for contempt of court, was sent to a hospital outside for observation on Aug. 6, days before the start of a corruption trial. 

“Mr Zuma underwent a surgical procedure on Saturday, with other procedures scheduled for the coming days. As a result, DCS is unable to predict a discharge date as our priority at this stage is for Mr Zuma to be afforded the best care possible,” the department said in a statement on Sunday.

He has been under medical supervision by staff from the SA Military Health Services since his admission at the Estcourt Correctional Centre.

Last week, a high court postponed his corruption trial to Sept. 9 after his hospitalisation. Zuma’s medical condition remain unclear and his legal team has been ordered by the judge to produce a medical report by Aug. 20.

The prosecutors may appoint a doctor of their choice to assess whether Zuma is fit to stand trial. 

Zuma, whose jailing last month ignited looting and unrest, faces charges with co-accused, French defence firm Thales, over a $2 billion arms deal corruption case that led to his sacking as South Africa’s deputy president in 2005.

Zuma and Thales have denied the allegations.