JAKARTA - People who clicked on the Finance Ministry's Directorate General of Tax website recently were greeted by a white "pocong", or ghost, on a blackened background and a line that said "thank you elze muahahahahah".
But the authorities are not laughing. The incident highlights a worrying trend - rising cybercrime in the country.
"This is just one of the 1.5 million attacks we see on Indonesian websites daily," said Mr Gatot S. Dewa Broto, spokesman for the Ministry of Communications and Information Technology. "Eight in 10 of these are to do with defacing websites... the rest are with data theft and other criminal acts."
Mr Gatot noted that cases of cybercrime have risen over 20 per cent from last year.
Indonesia ranks among the world's top five in the number of Facebook and Twitter users, but this also means that its population of 250 million is increasingly vulnerable to cybercrime.
American technology research firm Akamai, which monitors a third of the world's Internet traffic, claims Indonesia has overtaken China as the world's main source of hacking attacks, rising to 38 per cent this year from less than 1 per cent in previous years.
This does not mean, however, that all attacks originate from Indonesia as hackers have the ability to hijack IP addresses and disguise the source of their attacks, said Mr Gatot.
Echoing this view, information technology analyst Yungki Prabowo said: "The data reflects the outcome of increasing Internet speeds and bandwidths in Indonesia... making it easier and faster to hack or hijack if technology does not keep up."
Police have also recorded more cases of identity and data theft, as well as online scams. These have shot up by almost double since 2009, mainly due to more people surfing the Net using their mobile phones, and more reporting cases of cybercrime, police said.
One of the most common modes of online theft is to hack into e-mail, steal the identities and trick their victims into transferring money.
The biggest arrest this year involved a group - five Indonesians and one Nigerian believed to be part of a syndicate - who hijacked corporate e-mail accounts and managed to extract 5 billion rupiah (S$500,000) from unsuspecting clients.
Terrorism analysts warn that militants are exploring all methods to raise money for their cause. In at least one reported case, militants in the Sulawesi network led by Indonesia's most wanted terrorist, Santoso, siphoned off 8 billion rupiah from stolen bank account numbers.
According to Brigadier-General Arief Sulistyo, chief of the economics crime unit, there are five cybercrime departments across the country. "But we need more expertise and branches to cope with the rapid pace of Indonesia's inter-connectivity," he said.
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