Xolile Mngeni and his co-accused, Mziwamadoda Qwabe, are charged with the murder of 28-year-old Anni Dewani. She was found shot dead in an abandoned taxi in Cape Town’s impoverished Gugulethu township in November.

Mngeni’s defense attorney said his client was still undergoing medical tests Tuesday after being diagnosed with a brain tumor. Court proceedings had already been postponed in June to assess his condition.

Mngeni’s attorney says the trial is now set to begin Sept. 20.

A British judge is expected to determine Aug. 10 if 31-year-old Shrien Dewani will be extradited to South Africa to face charges for allegedly hiring the men to kill his wife.