European protests against the high price of fuel have now affected the Web site of the Organisation of Petroleum Exporting Countries.
It was taken offline on Wednesday after a message appeared on its opening page demanding its members act over the rocketing price of crude oil.
"I think I speak for everyone out there when I say you guys need to get your collective arses in gear with the price of crude," it said.
"We really need to focus on the poverty-stricken countries who don't even have enough money for aspirin, let alone exorbidant (sic) prices for heating oil."
The message posted by a person or group called "fluxnyne" did not affect the operations of the Web site.
The attack was reported by Attrition.org, which monitors internet vandalism. It also says the OPEC Web site www.opec.org was last hit in June.
OPEC has been in the spotlight after it restricted oil production to boost crude prices earlier this year.
Yesterday, it declined to comment on the attack on its Web site, or say why it was taken offline.
Meanwhile, the protesters have been using the latest technologies in their campaign.
The BBC yesterday reported that protesters have been using emails and mobile phones in planning and organising their blockades of oil terminals and motorways in the UK.