Another sad and strange story of horses abruptly losing their bearings and going "amok" this time, at Emerald Downs in Washington state. Humans and horses were injured; one horse, sadly, had to be killed.
Strange, and even stranger -- in February I posted a link to an odd story about race horses in England, linking to an article about horses mysteriously falling to the ground and dying. Some people at the racetrack reported feeling a tingling sensation as they walked across the grass.
[thanks to piglipstick for Emerald Downs link.]