Meta Platforms said on Wednesday it had removed about 63,000 accounts in Nigeria that attempted to engage in financial sexual extortion scams mostly aimed at adult men in the United States.

Nigerian online fraudsters, known as "Yahoo boys," are notorious for scams that range from passing themselves off as people in financial need or Nigerian princes offering an outstanding return on an investment.

Meta said in a statement the 63,000 accounts were on Instagram, adding that it had also removed 7,200 Facebook accounts, pages and groups dedicated to providing tips on scamming people.

The company also took down a smaller coordinated network of around 2,500 that were linked to a group of around 20 individuals.

In sexual extortion, or "sextortion", people are threatened with the release of compromising photos, either real or faked, if they do not pay to stop them.

The majority of the scammers' attempts were unsuccessful and although mostly targeting adults, there were also attempts against minors, which Meta reported to the U.S. National Center for Missing and Exploited Children.

Meta representatives said this was not the first time they had disrupted such networks, but added they were disclosing the current operation to "drive awareness."

The social media giant has been on the defense in recent years as governments, including legislators in the United States where Meta is based, ramp up pressure on it to address concerns that its executives have ignored evidence that its services harm children.

In a hearing earlier this year, one U.S. lawmaker accused Meta Chief Executive Mark Zuckerberg and other social media leaders of having "blood on their hands" for failing to protect children from escalating threats of sexual predation on their platforms.

The U.S. Surgeon General has also called for a warning label to be added to social media apps as a reminder of those harms.

Nigeria's scammers became known as "419 scams" after the section of the national penal code that dealt - ineffectively - with fraud.

As economic hardships worsen in the country of more than 200 million people, online scams have grown, with those behind them operating from university dormitories, shanty suburbs or affluent neighbourhoods.

Meta said some accounts were providing tips for conducting scams.

"Their efforts included offering to sell scripts and guides to use when scamming people, and sharing links to collections of photos to use when populating fake accounts," it said.