The General Elections Commission (KPU) has confirmed its official Web site, which shows the progress of the country's ongoing vote count after its 5 April polls, was defaced on Saturday evening, reported local daily The Jakarta Post.
Hackers replaced the names of some of the political parties in contention with a string of fabricated entries, the report said.
While names of the top three were left intact, fourth-placed United Development Party had its name changed to "Pink Grandfather Party" and the Democrats' Party, currently in fifth position, was renamed "the Party of Bottled Mineral Water". More than 13 other factions suffered a similar fate.
Beyond leaving cybergraffiti, the attackers appear to harbour a more malicious intent.
"The hackers tried to hack our data centre and recovery centre, which have seven security systems, starting from 6.30 p.m. But they failed. They only succeeded in hacking our Web site, which is part of the public domain," Akhiar Oemry, chairman of KPU's IT division, was quoted as saying.
The breach caused a four-hour outage but KPU's Web site was back to normal at 10.30 p.m. on Saturday, the report added.
