With a surprise tweet Monday, longtime Reddit general manager Erik Martin announced he's leaving the popular online community after six years. Martin has been an outspoken defender of free speech on the site, and he leaves as it finds itself at the center of a controversy over hacked photos of celebrities that Redditors have dubbed, "The Fappening."

Martin was one of only a few dozen employees who manage the 15th most popular website in the United States, where the daily number of visitors exceeds tens of millions. At once a place for book recommendations and the discovery of viral memes, Reddit’s hands-off attitude toward what is posted on the site has landed it under an unflattering spotlight a number of times.

While little was known about Martin’s departure Monday, he’s previously advocated against censoring Reddit and his departure comes amid yet another nude photo controversy.

Hard decision, but after 6 outstanding yrs I’m leaving reddit. Thank you to everyone who helped me along the way & made it an amazing ride! — erik martin (@hueypriest) October 13, 2014

Reddit’s own numbers indicate the site has received 174,088,361 unique visits from more than 186 countries. In August alone, more than 27 million Americans visited the site, according to Quantcast.com.

As general manager of Reddit, Martin has been credited with building up the massively popular Ask-Me-Anything interviews, creating the biggest-ever Secret Santa campaign and opposing corporate involvement in what is still an almost entirely user-run community forum. He’s done this all while becoming one of Time magazine’s most influential people in the world and helping organize Internet protests.

But he’s also been there for the growing pains. Reddit has made news of late for being slow to remove the r/Jailbait thread (forums are known as sub-Reddits), where users shared pictures of underage girls taken without their permission. (Martin publicly squared off against the r/Jailbait creators.)

While making it possible for users around the world to communicate anonymously, administrators have also been taken to task for hosting racist sub-Reddits, the Find Boston Bombers sub-Reddit (which turned into an erroneous harassment campaign) and PicsofDeadKids.

Martin was asked about the last forum and said he felt the page was “gross.” But consider, he said, if the name of the sub-Reddit was actually “Autopsy Photos” and the forum hosted nothing but historical autopsy photos.

“The point is I don’t want to be the one making those decisions for anyone but myself, and it’s not the business Reddit is in,” Martin wrote in an Ask-Me-Anything session. “We’re a free speech site with very few exceptions (mostly personal info) and having to stomach occasional troll Reddits like PicsofDeadKids or morally questionable Reddits like Jailbait are part of the price of free speech on a site like this.”

The circumstances surrounding Martin’s exit are murky, and his departure is certain to inspire a debate on the site, but it comes after a number of posts about the “Snappening.” Hackers claim to have posted a database of stolen Snapchat photos and videos (the company denied to International Business Times a breach had taken place) of underage users.

If the Snappening sounds familiar that’s because it comes only a short time after the “Fappening,” in which personal pictures belonging to dozens of celebrities were stolen and uploaded to 4Chan. From there, the pictures were later uploaded to Reddit and removed days later, with site administrators electing to do so because the images were stolen. It was later revealed Reddit attracted enough Web traffic through the Fappening to power its servers for nearly a month.

“We understand the harm that misusing our site does to the victims of this theft, and we deeply sympathize,” Reddit CEO Yishan Wong wrote at the time, remarking on controversial sub-Reddits in general. “Having said that, we are unlikely to make changes to our existing site content policies in response to this specific event.”