Facebook has banned 50s advertisements on its website as part of an effort to crack down on the spread of counterfeit goods.
The social network said the advertisements were created by third parties and had been detected by users in the United States, Canada, Germany and the United Kingdom.
The company also said it was blocking ads from fake social media accounts, but would not give details of what the accounts had been doing.
Facebook users have complained about fake ads appearing on their sites in recent months, and the company has previously cracked down on bogus accounts and banned accounts believed to be behind them.
The move comes amid growing concern about the spread and misuse of the increasingly popular online dating site.
The crackdown follows reports of fake ads being used to promote products or services in China, which has become a focus of a growing crackdown on counterfeit goods after a string of high-profile fake products and services were reported to be being sold on the site.