This fighting is occuring in areas not far from the Thai border – close to both Mae Sai and Tachilek. I imagine The Irrawaddy will continue to update their coverage of what is but the latest episode in decades of skirmishes and pitched battles.
In one style of interpretation, this is just another classic “dry-season offensive“.
Given the sometimes problematic delineation between the relevant areas of Chiang Rai’s Mae Fah Luang district, and adjacent parts of the Shan State – and the chaotic nature of these battles – there is always a chance that fighting will spill into Thailand. This is one reason that Western governments still discourage their citizens from travelling to most places along the Thai-Burma border.