So I pass up the Khajiit merchant and his fellows as he's leaving Whiterun, I walk for about 2 minutes and a dragon swoops around me. He just keeps on swooping and won't land, but the combat music is playing. He's too high up for my arrows or magic to hit him (why?)... he eventually flies off, and fades out of view. I think nothing of it...
On my way back to Whiterun several in-game hours later, I come across a few "burned corpses" and a few weapons laying on the ground next to them.
I think that dragon just killed my Khajiit friends