NEED DONE BEFORE 12pm EST What method of germ warfare did the mongols use to spread the plague to italian merchants in the crimean peninsula?

This narrative contains some startling assertions: that the Mongol army hurled plague-infected cadavers into the besieged Crimean city of Caffa, thereby transmitting the disease to the inhabitants; and that fleeing survivors of the siege spread plague from Caffa to the Mediterranean Basin.