I believe these are actually stray dogs with a very severe case of "mange"; and mamalian skin desease, believed to be caused by mites that burrow into the animal's skin.
This desease causes the hair on parts, or all of the body to fall out, and the exposed skin to turn a leathery festering pink or gray.
Mange is very contageous among animals, so it's very possible that a group of stray dogs all contracted the desease, and are accounting for the multiple sightings.
Also, severe mange can cause an animal to become lethargic or irratable (if I had a colony of parisitic insects living under my skin, I'd be pretty pissed too), which would account for the animals growing at animal control officers.
my 2 cents worth.