The pics were posted on the social network Weibo.
The images show a plastic case that looks pretty much like what equips the iPhone 3G.
The speakers, microphone and headphone jack are exactly in the same place as on the iPhone 5.
An additional indication is also the new Apple Lightning cable connected at the bottom of the unit, which seems to authenticate the object as an iOS device.
However, we must remark the absence of the Apple logo on the back of the device.