Agreed, be careful about the Uygur and Tibetan men in Chengdu, I swear to God it is not racist! Most thieves with the descent of Han and other minorities are usually not very violent in Chengdu, I can not say they are safe but at least relatively not very violent, compared with the Uygur. Even the most Uygur pedlars I’ve saw on streets were very rude and they even force you to buy their poisonous rice cake (it is said that the cake has mercury within). So how can you imagine what a Uygur thief would do to you?
So if you want safety, you must try to keep away from these Uygur as you can, it is not racist, trust me. And you know the Law here is flawed, the Police would not give a shit most of time, maybe they treat foreigners better, but it is better to be smart yourself.