Facebook and Instagram are banning private gun sales on their platforms.
Facebook, which has 1.59 billion monthly users, already prohibited people from using its site to sell marijuana, pharmaceuticals and illegal drugs.
"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 an email statement.
The company specified that it is hoping to crack down on the peer to peer sales of weapons on Facebook.
It said that licensed firearm retailers will still be able to post about their goods and services on Facebook, with transactions of sales taking place off of Facebook.
Facebook said that it has systems in place to detect private gun sales and that it will remove content that violates its new policy.