The following exert is an eye witness statement. Please read into it what you will. This has been reported to mufon who I am sure are investigating:
Whilst smoking outside my flat i noticed one cloud that looked like a rain cloud in a totally clear sky. i showed it to my gf as it looked so out of place. and i asked what the weather conditions are for just that one cloud to exist right there in a clear sky. for some reason i took a few pics of it. after going in i started playing around with the image not using filters just changing the exposure brightness hue etc using my phone. no gimmicks. as i did some very strange things appeared. you can see at the top of the altered images something that that looks like a boot. which in other pictures shows a kind of vortex coming down from it into the cloud. also a very demonic face appears in the cloud. in one of the original pics if you zoom in on the centre of the cloud you can see a dark disk shape i didn’t see that at the time.