JOHANNESBURG - The National Prosecuting Authority (NPA) on Sunday announced that it has withdrawn murder charges against the 270 miners arrested by police for suspected involvement in violent activities during labor unrest last month.

But the NPA said that it would lay murder charges against the miners once all investigations into the matter are completed.

"At this stage the investigations in this matter are far from being completed," said Advocate Nomgcobo Jiba, acting National Director of Public Prosecutions.

"The murder charge against the current 270 suspects, which was provisional anyway, will be formally withdrawn provisionally in court on their next court appearance. Other provisional charges will remain," Jiba told a press conference in Pretoria.

The NPA on Thursday announced its decision to bring charges of murder, attempted murder, public violence, illegal gathering, possession of dangerous weapons and possession of firearms and ammunition against the miners for allegedly murdering their colleagues in labor unrest sparked by a wage protest. The legal move has drawn criticism from government officials as well as from the public.

The miners were arrested after police shot dead 34 miners in clashes after 10 people, including two police officers, were killed in violence linked to rivalry between two trade unions vying to gain dominance among the miners at the Lonmin Platinum Mine in Marikana, the North West Province.

The detained miners' lawyers have demanded their release in a letter to President Jacob Zuma. But the presidency said Zuma would not interfere in judicial affairs.

According to the NPA,  the miners would be released conditionally on warning and their case postponed pending the finalization of investigations, including the investigations by the Commission of Enquiry set up by President Jacob Zuma.

The release of the miners will be done in phases as police were trying to identify their residential addresses, Jiba said.

"Those whose physical residential addresses that the police have been able to verify will be requisitioned for court tomorrow and an application made for their release from custody," she said.

By Saturday night the police had been able to verify 140 of the miner's addresses.

"Those whose physical residential addresses have not been confirmed by the police will remain in custody until the next court appearance on Thursday," Jiba added.

Jiba defended the NPA's decision to institute murder charges against the miners, saying the decision  had been "based on a sound legal principle which has not only been part of our legal system for decades, but continues to remain relevant and applicable in our democratic dispensation".