Could be a black-tailed (or in this case, blue-tailed) Buff Old English Game Bantam. They're matched in color, so it seems unlikely that they're crossbreeds. @JedJackson probably has a better idea. Can you get a closer picture, preferably a side-view?
I agree with sylviethecochin. White legs and slender builds probably means they are Old English game bantams. They come in just about every color, so blue tailed buff is probably the variety. Or they could be OEGB crosses.