Reddit has stopped working properly, with subreddits and posts failing to load.
The company confirmed on its status page that it was looking into issues being experienced by users.
"We're currently investigating an issue with subreddit and post pages failing to load," it wrote on its website.
Reddit's "error rate" graph, which tracks how many times it has been unable to fulfil a users' request, also showed a surge of problems.
Despite the problems, many people still seemed to be able to load at least some of the site, and the issues appeared to be limited to certain users.
But even when pages were working, they did seem unusually slow to load.
Reddit rarely has major problems with its site. Last week, for instance, it was hit by issues, but they were specifically limited to whether polls worked properly.
The site does however get hundreds of millions of visitors each month, and so even the shortest or most niche problem can immediately have a significant impact.
