Ancient texts suggest that 3,300 years ago the Hittite empire used biological weapons against their enemies. The delivery system: Sheep.

According to a new review of Middle Eastern history, the Hittites sent infected herds into neighboring countries to weaken the populace. Once behind enemy lines, the sick sheep spread tularemia, a debilitating bacterial illness that can kill 15 percent of those infected.

In the 1330s BC, scholars and kings wrote of a “Hittite plague” that swept through a Phoenician city, crippling the citizenry. A few years later, the Hittites attacked. However, not quite grasping the power of their own weapon, the Hittites plundered the city and returned home with riches and, yes, infected animals. And so the cycle continued.

Using animals as WMD continued throughout history. The Soviets unleashed tularemia-infected rats to hold off the German invasion of Stalingrad during WWII. Archives show that half of the Nazi prisoners taken during that battle suffered from tularemia symptoms. And Canadian microbiologist Siro Trevisanato, who authored the Hittite review, told the New Scientist that tularemia is still a problem in Eastern Europe.

(Illustration: Monster-Watch staff)