The main website and a sub-site devoted to the diplomatic documents were unavailable from the U.S. and Europe on Wednesday, as Amazon servers refused to acknowledge requests for data.
Availability of the sites has been spotty since Sunday, when it started to come under a series of Internet-based attacks by unknown hackers. WikiLeaks dealt with the attacks in part by moving to servers run by Amazon Web Services, which is self-service.
Amazon.com Inc. would not comment on its relationship with WikiLeaks or whether it forced the site to leave. Messages seeking comment from WikiLeaks were not immediately returned.