It seems the default www.reddit.com/r/news subreddit, which has 9M subscribers, has been censoring, removing, and locking threads related to the shooting in Orlando.
It will be interesting to see how Reddit deals with this. One of the worst mass shootings in US history, and the main subreddit to discuss the situation is heavily censoring the coverage.
No mention of the shooting on the front page of Reddit currently (9 hours after it started): https://www.reddit.com/ (Screenshot: http://i.imgur.com/mMCx5bU.jpg)
Censored megathread (See how many comments have been deleted)- https://www.reddit.com/r/news/comments/4nql8f/orlando_nightclub_shooting_megathread/