Then he marched on Khorasan and Persia, and here the Mongols attempted genocide. No other word really seems appropriate. Writing shortly after the events in question, the Muslim historian Sayfi Heravi said the Mongols killed 1,747,000 when they sacked the city of Naishapur, killing everything down to the cats and dogs. At the city of Herat, he put the toll at 1,600,000. Another Persian historian, Juzjani, claimed that 2,400,000 died in Herat.
