I hear they are pretty intense in my area, especially to foreigners. It was a little stressful but I saw they had a clipboard with addresses so they were just knocking randomly. Yeah I was a little perplexed that they did that. Apparently there is a new law in China that pretty much gives the police the right to go in and take our stuff. If they have "probable cause" or they suspect us of being spies. Seems like China isn't too welcoming for foreigners anymore.