It's more complicated than that, since the other armed groups (also made up of Han and other ethnicities using Southwestern Mandarin as a trade language) currently preparing to seize the town have signaled they plan to shut down the scam centers. Meanwhile, the group they're attacking were acting as local proxies for the Burmese government, but it appears their arrests were at the hands of Burmese police.

Maybe the Burmese junta expects the rebel offensive to succeed and decided to get rid of soon-to-be-useless proxies for an easy diplomatic win, or they think the rebels are receiving clandestine support from the PRC in return for their promise to shut down scam centers and want to undermine that, or this could simply be infighting with the other police/mafia families in town.