(Bloomberg) -- While South Africans worry about the prospect of blackouts thanks to protests at power utility Eskom Holdings SOC Ltd., the company’s own office lights just went out.

Workers are picketing at the northern Johannesburg headquarters, as well as blocking the entrance to power stations around the country after Eskom, which supplies almost all of South Africa’s power, insisted it can’t afford a pay increase this year.

“Power supply has just been ‘mysteriously’ cut off at Eskom head office Megawatt Park,” spokesman Khulu Phasiwe said on Twitter.

The state-owned company, which got a new board and chief executive officer this year, is struggling to overcome years of poor management and financial performance amid a series of corruption scandals. Protesting workers have hindered access to some power plants and executives said they can’t guarantee that power supply will be maintained.

Legally the workers aren’t allowed to strike because the provision of electricity is considered an essential service.

To contact the reporter on this story: Antony Sguazzin in Johannesburg at asguazzin@bloomberg.net

To contact the editors responsible for this story: Antony Sguazzin at asguazzin@bloomberg.net, Liezel Hill

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