"Seacom has been able to add significant capacity to the network today and as a result has restored services for the majority of customers across southern and eastern Africa," Seacom said.
The cable had suffered an outage that saw internet services in SA and elsewhere slow as congestion built.
The company speculated that the cable was cut in the Mediterranean Sea and dispatched workers to remedy the problem.
Seacom said that most of the internet services have been restored.
"In addition, over the last 36 hours, we have been able to augment the IP network to relieve congestion. All customers whose services are restored are being contacted directly to advise them of the circuits now in service."
The outage mainly affected rich media services like video streaming.
The likely cause for the break was a ship dragging its anchor, Seacom said.
"However we suspect, based on our experience with sub-sea systems and the nature of the sea area where the cut has occurred, that the most likely cause is external aggression to the cable most probably caused by a larger vessel dragging its anchor across the sea bed," said Seacom CEO Mark Simpson.
The company tries to protect the cable, but hazards remain, he added.
"Unfortunately this remains a common cause of damage to cable systems globally, despite our continued efforts to protect the cable with armour, burying, notifications to ships of cable location and exclusion zones."
Seacom said that it would soon complete the restoration of the infrastructure.
"Work will continue overnight to bring further capacity into the network with a view to completing the restoration activity as soon as is possible."
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