The Anonymous group claimed on Wednesday to have published the IP addresses of 190 visitors to child pornography forums.
In a statement posted to pastebin.com, Anonymous said it was exposing the IP addresses as part of a campaign dubbed "Operation Darknet."
The exposed IP addresses belong mainly to users in the United States, Europe, Latin America.
Anonymous said it captured the IP addresses of visitors to child porn forums by tricking users into downloading a fake update to Tor software, which can be used to obscure an Internet user's identity.
During a 24-hour period last week, Anonymous said it captured the unique IP addresses of 190 visitors to child porn forums.