The Web page posted by a group calling itself "S-11" completely obscured Nike's site.
The page said "global justice is coming--prepare now," and it called for action at September's World Economic Forum 2000 in Melbourne, Australia.
The top of one page on the site contained the words "shut down the world economic forum."
The 2000 Olympic Games are set to begin Sept. 16 in nearby Sydney, Australia, and Nike is a major corporate sponsor.
Nike computer technicians were regaining control of the site, spokesman Vada Manager said today.
"We're backtracking now to find out how this happened," Manager said.
Nike has faced repeated criticism by student and labor rights groups for years over conditions at contract factories overseas, especially in Asia and Latin America.
The Beaverton, Ore.-based athletic shoe and clothing company has worked to improve conditions, hiring monitors and creating executive positions to deal exclusively with labor rights.
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