On Friday, Facebook announced a ban on private gun sales on the social network and the Facebook-owned photo platform Instagram.

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Recent mass shootings have fueled the debate over gun violence in the U.S. and led gun safety groups, states' attorneys general, and President Barack Obama to pressure the company to change its firearms sales policy.

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“Over the last two years, more and more people have been using Facebook to discover products and to buy and sell things to one another,” Monika Bickert, Facebook’s head of product policy, said in a statement to Reuters. “We are continuing to develop, test and launch new products to make this experience even better for people and are updating our regulated goods policies to reflect this evolution.”

For those who do not own guns or seek them out online, it may come as a shock that the social network has become such a popular platform for buying firearms, which is typically thought to take place on the darknet. But there are numerous public pages and private Facebook groups devoted to gun enthusiasts and those seeking weapons and ammunition.

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In 2014, a VentureBeat reporter arranged to buy a semiautomatic rifle and 90 rounds of ammunition from a member of the “Firearms Only Alamogordo” group and was told over text message that he need not show identification to make the purchase.

"We are certainly aware social media is being used to sell firearms," Bureau of Alcohol, Tobacco, Firearms and Explosives Special Agent Helen Dunkel told the site.

Facebook first amended its gun policy that year, making gun advertisements not viewable to minors and changed its regulated goods policy to prohibit illegal drug sales.

In early January 2016, President Obama issued an executive order prohibiting online gun sales across state lines and requiring more extensive background checks, and Friday's ban suggests that ammo-seekers may have to head back down the Silk Road.