Facebook has been swamped with complaints as users are convinced old private messages are being published on their public timelines.
Complaints have come from users in Britain, America and Europe, who said the private messages were sent between 2007 and 2009, the Telegraph reported.
However, the social networking site has denied the claims, saying there had been no privacy breach as the messages were old public posts that were being re-posted because of a bug.
"A small number of users raised concerns after what they mistakenly believed to be private messages appeared on their timeline," a Facebook spokesman said.
"Our engineers investigated these reports and found that the messages were older wall posts that had always been visible on the users' profile pages. Facebook is satisfied that there has been no breach of user privacy."
Colleen Taylor, a writer for an American technology website, wasn't convinced, however.
She told the Telegraph she had confirmed with friends that messages appearing in their timelines were originally sent as private messages.
Another user in London, said the same thing had happened to her.
"This is worrying. I'm trying to figure out how to fix it. It's scary. They are private messages and my friends and I used to discuss private things on Facebook," she said.