Telco StarHub has apologised for its service disruption yesterday after some of its customers reported that they were unable to access the Internet in the evening.

At about 9.50pm yesterday, StarHub said that its mobile data services were fully restored about four hours after customers began experiencing disruptions, and that most affected fixed Internet connections were also restored.

In a Facebook post at around 6.40pm yesterday, StarHub said it had received reports of issues with Internet access and was investigating.

An update 15 minutes later said that it was progressively restoring services, and that some of its customers may experience "temporary data congestion".

At about 9.50pm, the telco said most of its services had been restored. "We are sorry for the inconvenience caused by the incident this evening. Mobile data services for customers are fully restored. We have restored most of the affected fixed internet connections," said StarHub.

"We would like to thank our customers for their patience and understanding," it added.

It is not known what caused the disruption in StarHub's services.

This came after tracking website downdetector.com suggested at about 6pm yesterday that there was a widespread Internet outage with three Internet service providers across the island.

However, Singtel and M1 said there were no issues with their Internet services.

Singtel said in a statement that there had been some concern over Internet access across the island, but clarified that "our networks and systems are all fine".

M1 also clarified that there were no problems with its Internet service. A spokesman said: "We did not encounter any network equipment issue nor receive customer complaints on Internet access."

Yesterday evening, after StarHub announced that it was facing issues, Singapore's electronic payment network Nets said some of its services were affected.

In a notice on its website, Nets said: "StarHub is experiencing Internet connectivity issues and this has impacted some of Nets' payment services.

"We understand that StarHub's engineers are investigating and working to resolve the issues. We apologise for any inconvenience caused."