British tourist detained by US authorities for 10 days over visa issue

Earlier this month, the Guardian also had an article of a German tourist who crossed over the land border (San Ysidro Port of Entry, I assume) who was detained for a long while too. The details seemed kind of similar to this situation where it involves suspicion of tourists working in the USA without the proper authorizations.

While I don't like the whole "detaining people instead of just turning them around", but the German you are referring to was a tattoo artist who had posted on their instagram that they were doing pop-up tattoo events in LA, and then tried to enter on a tourist visa. She very much was in violation of the law, in other words.