Several government websites were unavailable for a few hours last Saturday because of a technical glitch, and not because they had been hacked into.
The Infocomm Development Authority (IDA) said yesterday that the glitch had occurred during maintenance work to beef up security.
"At no point was it a hacking attempt," said an IDA spokesman at a press conference in the evening.
Government agencies had been on heightened vigilance to enhance the security of their information technology systems since global hackers group Anonymous made threats against them last Thursday.
Over the next few days, some government websites may experience intermittent access while maintenance continues. Agencies will try to complete the work as soon as possible, said the spokesman.
To bolster their resilience, selected government websites had to be taken offline for maintenance. But last Saturday, between 1pm and 3pm, a combination of Internet routing issues and hardware failures caused a glitch, which took the websites offline longer than expected. This was rectified by 5.20pm, said IDA.
Websites of the Singapore police and the ministries of Home Affairs and Foreign Affairs were among those affected by the glitch. Unaffected websites included the Central Provident Fund, Inland Revenue Authority of Singapore and Ministry of Defence.
Last Thursday, a YouTube video posted by "Anonymous" threatened to bring down Singapore's infrastructure in a show of protest against licensing regulations on news sites.
Instituted in June, the regulations require selected news sites with at least 50,000 unique visitors from Singapore each month over a period of two months to post a $50,000 bond and take down content against public interest or national harmony within 24 hours.
"We demand (that) you reconsider the regulations of your framework or we will be forced to go to war with you," said the video message, delivered by someone wearing a Guy Fawkes anonymity mask.
The threat last Thursday followed attacks mounted on Ang Mo Kio Town Council's homepage on Monday last week and an earlier hacking of a webpage within pre-school operator PAP Community Foundation's site by someone known as "The Messiah", who also claimed to be part of the Anonymous collective.
Last Friday, a section of The Straits Times' website was attacked, with "Messiah" claiming responsibility.
These recent cyber intrusions gave rise to speculation that last Saturday's downtime may have been an extension of the attacks.
"The Singapore Government takes cyber security and threats to its IT infrastructure very seriously," added the IDA spokesman yesterday.
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