Johannesburg - The SA Municipal Workers' Union (Samwu) is conducting its own investigation into the strike by a few hundred City Power workers earlier this week, the organisation said on Sunday.
"We are conducting our own investigations into the matter. We will not be giving any further information until we receive the outcomes of those investigations on Monday," Samwu spokesperson Tahir Sema said.
The investigations would look into the strike which started on Wednesday, the demands of the workers, the alleged sabotage of sub-stations which resulted in widespread power outages in parts of Johannesburg and what can be done to resolve the situation, Sema said.
On Saturday, City Power spokesperson Sol Masolo said the power supplier was working with the police to identify those responsible for cutting the power supply around Johannesburg.
"An investigation was continuing but no culprits have been identified," he said
No arrests had been made on Sunday.
The power outages in large parts of Johannesburg since Thursday, have been blamed on sabotage, allegedly by workers who embarked on an unprotected strike on Wednesday.
The workers are believed to have downed tools after City Power introduced a new shift system to reduce its increasing annual overtime bill.
By noon on Saturday power had been restored to all areas in Johannesburg.
Earlier on Saturday, Masolo said City Power had met with two unions, Samwu and Independent Municipal and Allied Trade Union (Imatu) over the strike.
"In the meeting, which was an 'information-sharing session', City Power indicated its concern about the manner in which striking employees disrupted the network," Masolo said in a statement.
The company said it had committed itself to negotiating with the two unions only due to "formal channels previously agreed on". Masolo did not elaborate on this.
Imatu was not immediately available for comment.