Crooked Ninja Turtle Gang
The Crooked Ninja Turtle Gang is a gang of martial arts students from Smash's Slash for Cash Dojo. Shredder recruits members from the dojo, and have them committing crimes disguissed as the turtles, to trick people into believing the turtles are behind the crimes.
They appear in the the TMNT Adventures Return of the Shredder.[1][2] In the comic they appear wearing turtle outfits and red headbands akin to Raphael's, and are more evident as giving the appearance of humans in Ninja Turtle costumes.