Johannesburg - Head of the Special Investigating Unit, Vas Soni, has resigned, the organisation said on Monday.
He resigned for personal reasons, spokesman Sefura Mongalo said.
“His wife has not been well for the past five months,” he said.
Soni told broadcaster eNCA he needed to spend time with his wife.
When asked whether the job had been stressful, Soni said it had.
“I think it has been stressful and it's a serious challenge... I had spent almost my entire working life in the private sector and did not realise what a challenge working in the public sector is,” he told the broadcaster.
Soni, an advocate, was appointed by President Jacob Zuma in September 2013. He indicated he would be going into private practice.