The official website of Singapore Prime Minister Lee Hsien Loong was hacked by apparent members of international hacking collective 'Anonymous' late Thursday – the latest episode in the string of cyber-attacks in the city-state.
The hackers posted an image of a Guy Fawkes mask, a well-known symbol for the group, with the words "It's great to be Singaporean today" on a section of the website of the prime minister's office.
The affected section was taken down soon after the hacking incident, which took place at 11.17 pm local time.
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The attack came a day after the prime minister said the government would "spare no effort" to track down and bring to justice those who threaten to attack the country's computer networks.
ICT regulator Infocomm Development Authority of Singapore (IDA) said it is still in the process of investigating the incident.
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"We will continue to strengthen all Government websites. This includes the checking and fixing of vulnerabilities and software patching. While this is in progress, visitors to Government websites may experience intermittent problems with access. This will be completed as soon as possible," a IDA spokesperson told CNBC.