Former State Security Agency top spy, Thulani Dlomo, has handed himself over at the Durban Central Police Station.
He was accompanied by his lawyer Phumlani Shangase.
The ambassador to Japan has told SABC News that he fears for his safety and that of his family.
Dlomo says his lawyer called him to meet him at the station because of his intention to hand himself over to the police.
His decision comes after allegations that he is among those responsible for fuelling the unrest that started in KwaZulu-Natal and spread to Gauteng.
On Thursday, acting Minister in the Presidency, Khumbudzo Ntshavheni, revealed that one of the 12 masterminds of the riots that have claimed more than 70 lives had been arrested.
She said police were still pursuing the other 11.
Former State Security Agency top spy hands himself over to police:
Ramaphosa’s expected address
On Friday, Minister Ntshavheni announced that President Cyril Ramaphosa will address the nation on Friday night at 20:30.
The address to the nation follows the president’s oversight visit to some parts of KwaZulu-Natal.
The president has admitted that his government could have handled the violent unrest in Gauteng and KZN, but there were some lapses in the process.
Ntshavheni has told a media briefing in Pretoria that the president will give a way forward on more needs to be done for the country to move forward.
Acting Minister in the Presidency Khumbudzo Ntshavheni briefs the media:
Gauteng and KwaZulu Natal update
Ntshavheni says the death toll from recent violence and looting in Gauteng and Kwazulu-Natal has risen to 212.
She says the situation has stabilised in most parts of the country.
“Additional, six deaths were reported and cumulative deaths have now become 32 in Gauteng; 137 additional arrest were made and South African national Defence force deployment supporting the SAPS remains in Gauteng in the potential hotspots. In KwaZulu-Natal 1 488 cases were reported overnight additional 89 deaths were reported. Cumulative number of deaths in KZN its 180 and law enforcement continue to closely monitor the situation in that province which is stable,” she says.