The National Union of Mineworkers said on Monday that 10% of its 15000 members at Eskom had embarked on a strike after wage negotiations failed.

Paris Mashego‚ the union’s Eskom energy sector coordinator‚ said members had downed tools at Thuthuka‚ Matla‚ Dover and Arnot power stations but warned about the possibility of a full-blown strike by Wednesday.

Eskom spokesman Khulu Pasiwe said employees were not supposed to go on strike as the power utility was classified as an essential service.

“The normal human resource processes are going to unfold for people involved in the unprotected strike‚” said Pasiwe.

Eskom received reports at 2am on Monday that a road leading to Arnot power station in Mpumalanga had been blocked. Pasiwe said police had unblocked the road and brought the situation under control.

“People who are meant to go to work are at work. All 27 power stations are operating as per normal at this stage.”

Eskom is concerned about staff working on late shifts. “When people go on strike‚ they sometimes intimidate others. The matter of dealing with intimidation falls within the ambit of the police‚” said Pasiwe.

NUM members are on strike as they are not happy with a salary offer made by Eskom.

Employees are demanding a 12% wage increase for the highest-paid staff and 13% for the lowest-paid‚ to be allowed to sell service and occasional leave and they want the housing allowance to be increased from R2600 a month to R5000 a month.

Eskom has offered employees a 7% increase.