Seacom announced on its website that service between Mumbai and Mombasa had been interrupted.
"We note Seacom services between Mumbai and Mombasa are down since 09:19 GMT/5th July 10. We are still investigating," the company said, adding that more details were to follow.
In April there was also a service breakdown and Seacom said at the time that it was related to a Mediterranean section of the line.
"Seacom experienced an interruption in its network on 14 April 2010 which lasted around seven minutes as a result of a fault on the Mediterranean section of the SEA-ME-WE 4 submarine cable system, which Seacom currently utilises to connect to London," Seacom said on its website.
Internet service providers said that traffic was routed over the SAT3 connection, but it negatively affected traffic.
Seacom has not revealed the cause or nature of this latest interruption. The company said it was investigating the incident.
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