Were you one of those who were curious about the images which appeared on subsites of the Prime Minister's Office and the Istana? Did you click on the URL posted on some forums?
Well, your computer may now be infected with malware or viruses, said the Infocomm Development Authority (IDA) last Friday.
Between 11pm on Thursday and 12.20am on Friday, hackers created an alpha-numeric code which, when pasted on a search engine of the two sites, led to pictures posted by the hackers.
But IDA said the two subpages were removed within 15 minutes and that they are taking measures to strengthen all government websites.
This comes after an alleged call by the hacker collective Anonymous to mark Nov 5 with a protest.
On that day, a spike in hacking activity showed up on IDA's radar.
Despite unusually high traffic to many government websites on Nov 5, IDA said there were no successful cyber intrusions or denial-of-service attempts on both transactional and non-transactional government sites.
But even a hacking attempt is illegal and could be punishable under the Computer Misuse and Cybersecurity Act, said criminal lawyer Rajan Supramaniam.
"Once you make an attempt, there is an intention to hack. If you're traced and caught, you have to be prepared to face the consequences," he said.
Last week, Anonymous allegedly threatened to bring down Singapore's infrastructure in a show of protest against the Internet licensing framework.
On Wednesday, Prime Minister Lee Hsien Loong said the Singapore Government "will spare no effort to track down" anyone who attempts to bring down the Republic's cyber infrastructure.
Cyber security experts told The New Paper on Thursday that a lot of resources are needed to track down these hackers.
But experience shows it can be done despite sophisticated tactics employed by hackers to cover their tracks.
Mr Alex Nian, manager of IT firm SecureIT-NET, said hackers usually gather networks of infected computers - known as botnets - by hacking into PCs and installing malware in them.
They then use botnets to carry out hacking activities, such as denial-of-service - making a network/service unavailable to users by diverting a high amount of traffic to the website - or remotely controlling the botnets to hack into government servers.