THE South African police on Monday confirmed the death of one of the investigators in the Thabo Bester prison escape case.

National police spokesperson Brigadier Athlenda Mathe said they were still probing the circumstances surrounding the death of the investigator, who was also the police's provincial head of organised crime.

Media reports show that 59-year-old Brigadier Jackson Mkhaulesi took his own life.

It reported he had been seen in the Bloemfontein High Court earlier on Monday, where Dr Nandipha Magudumana's urgent application to declare her "deportation" from Tanzania unlawful was dismissed.

The publication reported he left the court after the verdict and drove to the state garage in Hamilton, where his body was later found in his car.

National police commissioner Fannie Masemola said Mkhaulesi was a "hardworking, loyal and dedicated detective" and had been an expert in crime detection.

Masemola said he served the police for 31 years and his death would leave a void in the service. 

"Over the years, he has proven himself a highly skilled detective with a wealth of experience and knowledge in crime detection.

His departure leaves a void in the SAPS detective environment. On behalf of the SAPS, our sincerest condolences to the family, friends and colleagues of our officer.

Mathe added Mkhaulesi's family and colleagues would receive counselling from the police's Employee Health and Wellness.