Facebook on Wednesday announced major policy changes related to the use of its website (and popular photo sharing app Instagram) for marketing illegal firearm sales amid pressure from gun control groups. "We will not permit people to post offers to sell regulated items that indicate a willingness to evade or help others evade the law," Monika Bickert, Facebook's head of global policy management, said in a press release.

The change in policy means that Facebook will not permit private sellers of firearms in the US to sell guns without background checks or across state lines. Posts about the sale of a regulated item will be limited to people over 18 years of age, and if an Instagram user searches for sales or promotions of firearms, the company would display messages about gun laws.

Facebook said it would rely on users to report anything that violates the company's policies, including offers to illegally sell guns, adding that the company will remove reported content, and notify law enforcement when necessary. The policy changes will be implemented and enforced within a few weeks.

The ease with which children could potentially buy guns through Facebook has increased over the last few months. Last week, VentureBeat reported that buying a gun on Facebook takes merely 15 minutes.

It's a small but auspicious victory for gun control groups like Moms Demand Action (formed after the Sandy Hook Elementary School massacre), who have been demanding tighter restrictions on the marketing of guns through social media. New York Attorney General Eric Schneiderman, who had been in talks with Facebook over its gun policies, said that it is "probably the strongest step ever taken to end" illegal gun sales on social media.