Wal-Mart, along with many other retailers like Macy's, Target and Best Buy, started its Black Friday sales on Thanksgiving this year — but the promise of deep discounts apparently caused some disturbing altercations.

The world's biggest retailer took pains to avoid the typical mayhem that accompanies its door-buster deals, from distributing wristbands to consulting with crowd-control experts. The retailer has sought to improve crowd management this weekend, particularly after one Wal-Mart worker was shockingly trampled to death on Black Friday in 2008. (The retailer still hasn't paid a $7,000 fine tied to that incident.)

But retailers were still unable to prevent a series of violent incidents at Wal-Mart locations across the country — many of which were documented under the hashtag #WalmartFights. Anonymous-linked Twitter account @YourAnonNews urged people to use the hashtag to tweet updates of fights throughout Thanksgiving evening (it's now trending as of 11:30 p.m. on Thursday) — and the results have been rather frightening.

Following is a sample of the tweets, YouTube videos and Vines so far — we'll continue to update with the most striking as they roll in (though hope there won't be more.)

Update - Nov. 29, 8:45 a.m., EDT: This update added more footage and tweets from the night.