Facebook apologized to Norway's prime minister for deleting a famous Vietnam War photo from her page on the social network, acknowledging the limitations of its computer-driven curation techniques.

Enlarge Image Courtesy of Aftenposten

Facebook Chief Operating Officer Sheryl Sandberg admitted the social network shouldn't have deleted a photo of a naked 9-year-old girl fleeing after a napalm attack. Facebook had said the photo, which won a Pulitzer Prize, contained child pornography.

"We don't always get it right,"

Sandberg wrote to Prime Minister Erna Solberg, according to the letter obtained by Reuters through Norwegian freedom of information rules on Monday. Sandberg promised "to do better" and thanked Solberg for helping Facebook "get this right."

The apology comes after Facebook, which is transitioning from human to algorithmic curation, set off a wave of public complaint in Norway last week for deleting the iconic photo from a host of the social network's pages following its publication in the Aftenposten newspaper.

The decision sparked backlash across social media for Facebook. Outraged users posted the "Napalm Girl" photo on their pages, and those images in turn were also deleted. On September 9, Aftenposten printed a public letter to Mark Zuckerberg, Facebook's CEO, urging the social network to allow the photo's publication.

A few hours after the public outcry began, Facebook reversed its decision, acknowledging the historical significance of the image. It has since adjusted its review algorithm to allow the image to be posted.

The website said its automated tools were behind the mass deletions. The tools have also been blamed for the posting of fake news in its Trending Topics section on multiple occasions.

Facebook confirmed that Sandberg sent the letter, but declined to disclose its contents.

Norway's prime minister, whose Facebook page was among those from which the photo disappeared, mocked the transgression with a censored version of the original.

On Saturday, Solberg commended Facebook for reversing its stance, but said the social network shouldn't allow its responsibilities to "be handed over to machines."

"This debate is about more than this one picture, and more than just Facebook as a network," Solberg wrote in a Facebook post. "It is about the responsibilities large media institutions and platforms have to not pervert or distort reality."