For weeks there have been backstage attacks during every episode of Impact where a card with a circled "X" was placed by each victim. Guys like Fallah Bahh, Sonjay Dutt, Jimmy Jacobs, and Joseph Park have been taken out since these attacks started.
After Petey Williams was seen at two of the scenes, Sonjay Dutt had him arrested on tonight's show. As the police officer took Williams away from the group, he ended up punching and choking Williams out with a nightstick. He then placed a card by Williams and revealed himself as the attacker. Although his name isn't officially known in Impact quite yet, he is known elsewhere as Killer Kross (Kevin Kross).
Debuting in 2014, Kross has worked previously for Global Force Wrestling, Lucha Underground (in dark matches), and more recently for AAA. In AAA, he's in a stable called MAD alongside Jeventud Guerrera and Teddy Hart.