Correctional Services said that “matters are under control” at Johannesburg’s Sun City Prison on Wed.
The race is on for the R50000 grand prize of the Spar women's 10km series.
The final race of the series, which takes place in Johannesburg on October 12, will determine who will walk away with the money.
Cape Town runner Zintle Xiniwe is leading the pack, after great performances in Durban, Cape Town and the most recent race in Tshwane.
But Xiniwe will not be in the country on October 12 when the race takes place, which gives her nearest rivals Poppy Mlambo in second place, Michelle Baartman and Gloria Baeba a shot at the grand prize.
On the day of the race, Xiniwe will be in Brazil competing in the World Half Marathon Championships.
"It is sad, but I think Poppy has a really good chance of finishing at the top. In Brazil, my aim is to improve my time and finish in the top 10," said Xiniwe.
Mlambo said: "I am going to give it my all this time.
"Last year I ran only four of the five races, but ended in position five. This year, I have already done the last four, and provided nothing goes wrong, will also compete in the last race."
The race will start from the Old Parktonians Club in Randburg, Johannesburg.