Five local men are being held for allegedly hacking the websites of Singapore's president and prime minister, police said Tuesday, amid a rash of cyber attacks in the city-state.
Police said in a statement the alleged hackers had "exploited a vulnerability" in both websites to display pages from other sources last week.
A "subpage" of the website of the Istana, the official residence of President Tony Tan, was hacked and displayed a crude image early last Friday, an hour after Prime Minister Lee Hsien Loong's website displayed mocking messages from international activist hackers' group Anonymous.
Police said the five suspects are local men aged between 17 and 45.
Another Singaporean, James Raj, was charged in court earlier Tuesday with hacking a local council's website and posting an image of a Guy Fawkes mask, the international symbol of Anonymous.
Raj was charged with hacking into the website of the Ang Mo Kio town council, a district whose team of MPs representing it in parliament is led by Premier Lee, on October 28, and posting the image.
The hacking took place three days before a self-proclaimed spokesperson for Anonymous demanded in a video that Singapore scrap a law requiring news websites to obtain annual licenses.
The new Internet licensing rules came into force in June and have angered bloggers and activists who say they are designed to muzzle free expression.
Singapore strictly regulates the traditional media, but insists the new licensing rules do not impinge on Internet freedom.