Notorious snitch Tekashi 6ix9ine still isn't lying low.

He was paraded in front of the fans at  UFC 266 in Las Vegas Saturday.

Not everyone in the house was a 6ix9ine fan, and someone in the crowd tossed a drink when he walked by and called him a "bitch."

6ix9ine tossed his own drink right back.  Tekahsi's drink was said to be coffee, which isn't fun to get hit with.

To add insult to injury, the fan was led away in handcuffs, whereas 6ix9ine was not.

That's what you get for messing with a federal worker.