The AOPA is reporting harassment of some private pilots by CBP, for flights which start, continue, and end within US borders.
Apparently some people have been detained for hours while agents tear up their planes & property.
Here's a letter from the AOPA to the CBP. Among other things, they're taken to task for trying to say that the response to the AOPA open records request (which apparently has a 20-day window) would take 6 months.
Here's their advice to pilots, in a form meant to be printed & carried.