Update at the Linda Moulton Howe article site.
It shows an interesting map of the area where some 18 different sites had some sort of mutilation investigation since 1979.
http://www.earthfiles.com/news/news.cfm?ID=1006&category=Environment
These deaths occured circa 10/11Oct05 with another group of 16 horses killed on the 22Oct05. The later group has the appearance of a lightning strike and explainable by authorities. The former group of 6 horses and mule, though all had quarter inch piercings, like a hole punch, generally between their eyes, with bruising, no bleeding or clotting, and no penetration to the skull. Puncture wounds were similar to a biopsy type procedure from one interpretation.