Correctional Services spokesman Manelisi Wolela has denied allegations that student leader Mcebo Dla.
An overstretched judiciary is hampering attempts to prosecute those responsible for mining accidents, the minerals and energy minister, Buyelwa Sonjica, said yesterday.
Mining companies in South Africa, the world's top source of platinum and gold, are under pressure to improve safety at mines.
Around 200 workers have been killed in mine accidents this year, prompting about 240000 miners belonging to the biggest miners' union to strike on Tuesday in a countrywide protest.
South Africa's National Union of Mineworkers said the stoppage was also aimed at urging the government to prosecute negligent mine managers.
"We are looking at tightening the mining health and safety policy, but the problem is to charge," Sonjica told reporters.
"We investigate the cases, we hand them over to the department of justice and because they have capacity limitations, we have a problem of seeing a completion of that process."
The strike affected output across the industry. Anglo Platinum said it lost a full day's output of 9000 refined platinum ounces, which helped to send the metal's price higher because of supply concerns.
AngloGold Ashanti lost a day's output but could not give an exact figure. Impala Platinum lost 3500 ounces of the metal.
Gold Fields, Harmony Gold and the coal producer, BHP Billiton, were also hit.
Miners have died in rock falls and explosions, making South Africa's mines among the most dangerous in the world.
The number of miners killed in 2006 was 199 and 202 died in 2005.
Sonjica reiterated government's stance of closing down the mining operation every time a death occurred.
"At the end of the day the culprit must be brought to book and, at this stage, we have not been able to bring the culprits to book," she said. - Reuters