South Africa's Eskom says four generating units back in service

An escalation of power cuts on Monday by struggling South African utility Eskom was caused by seven generating units tripping within five hours, but four had returned to service by the evening, Eskom's board said.

Eskom's board had an urgent meeting with Public Enterprises Minister Pravin Gordhan on Monday after the company implemented the severest power cuts in several years earlier in the day.

Three more generating units are expected back online by Tuesday morning, Eskom's board said in a statement, adding a lack of reliability at the Medupi and Kusile power stations was a serious concern. (Reporting by Alexander Winning; Editing by Mark Potter)