Brazilian police are trying to find the blogger who claims to be exposing the names of unfaithful partners online, the U.K. Daily Mail reported.
The unidentified blogger, from the small rural town of Lagoa da Prata, in Minas Gerais, reportedly has identified 300 supposed cheaters on a popular social networking site.
Some people whose partners' names are listed deny that any affairs are going on, the Mail said.
"My wife is a Catholic and a worker," said one man, who wished to remain anonymous. "I have never had cause to doubt her."
Another woman said she nearly broke up with her partner after the blogger posted his name, the paper reported.
"The military police are advising people to stay calm," said Brazil police officer Lt. Marcondes Couto, according to the paper.
"We are investigating and we will catch this criminal. Justice will be done."
It wasn't disclosed where the blogger was posting the list of names.