What on earth are the Shanghai authorities suggesting with this warning poster? We have to be aware of suspicious gatherings (at least I think that’s what it’s supposed to say), as well as weekly underground preaching.
I don’t think either of these would get past the politcal correctness police in the west but in China it seems acceptable to draw pictures of Muslims and warns people of them. 
The drawings are of a woman in a Burkha and men in Islamic headwear. It seems alright to have weekly preaching in a Christian church and in an overground mosque but not underground.
I wonder what the foundation of this fear is. In my experience, people of faith are generally nice and considerate and certainly don’t cause me to fear – quite the opposite. At least they have a moral compass which can’t be said for everyone.