In response to previous post:
http://www.rumormillnews.com/cgi-bin/forum.cgi?read=84993

That post linked to an image of material from 4chan/pol.

Here is the link to the 4chan thread, currently in an archive:

https://archive.4plebs.org/pol/thread/141096258

Here are links to the alleged "warnings" which are scattered in the thread:

https://archive.4plebs.org/pol/thread/141096258/#141100963

https://archive.4plebs.org/pol/thread/141096258/#141102703

https://archive.4plebs.org/pol/thread/141096258/#141104921

Some subsequent comments, after the mass shooting, speculate that the anonymous poster "John" is John Titor, the famous alleged time traveler of internet myth and legend, and that the reason the event didn't happen on the predicted day but in fact three weeks later was because John Titor has already altered the timeline by traveling back to our time period from several decades in the future, so that it is not quite the same as the timeline he left.

Here are the three main posts by "John" in text form:

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Anonymous ID:LAbNFEtv Sun 10 Sep 2017 23:08:36 No.141100963

look i feel bad for some of you on this website. so i'll let you in on a little secret. if you live in las vegas or henderson stay inside tomorrow. don't go anywhere where there are large groups of people. also if you see three blacks vans parked next to each other immediately leave the area. you're welcome
-john
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Anonymous ID:LAbNFEtv Sun 10 Sep 2017 23:28:12 No.141102703

it's called the "high incident project". they want to make the american public think that places with extremely high security aren't safe. they are trying to create more regulations. you will see laws proposed within the next few years to put up more metal detectors and other security devices. media and politicians will be saying places with lots of police need even more police. i can't guarantee anything will happen tomorrow but las vegas is on their minds.
-john
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Anonymous ID:LAbNFEtv Sun 10 Sep 2017 23:55:53 No.141104921

if their plan is successful state of nevada will pass a law in the future making all casinos have mandatory metal detectors and backscatter machines. soon after a federal law will be passed to put these machines in universities, high schools, federal buildings, you name it. osi systems and chertoff are the main producers of these machines. sometime around 2020 chertoff and osi will merge into a single company. after they merge the owners will sell off all their stock and make billions in profit. mr chertoff has been in contact with sheldon adelson. mr adelson will become a huge sponsor of these machines and he will be the first to put them in his casinos when the law passes. this is my last message for now. don't expect me to return anytime soon
-john
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