Koon pandiyan (கூன் பாண்டியன்) was a king who ruled Madurai around 7th century. He is infamous for his massacre of 8000 Jain priests during his reign. He is one among the 63 Nayanars.
During 5th, 6th and 7th century Buddhism and Jainism were the popular religions in South India. The king Koon Pandian also was maravar. But his wife Mangayarkarasi is a Saivaite. In the time the king got Boils (வெப்பு நோய்). The queen asked Sambandhar a saiva poet to come to Madurai to treat her husband. Accordingly Sambandhar came and treated the king with some hymns and some magic remedies like Camphor. The king got cured and Sambandhar asked him to kill the Jain priests.
The King Koon Pandiyan and Queen Mangayarkarasi were ordered to kill the Jain priests. The Jain priests were forcefully put over sharp, tall, conical structures (கழுமரம்) in sitting posture. Their bodies were pierced by those conical structures. In this way 8000 priests were killed. These things were happened in a village near Madurai called Samanatham (சாமநத்தம்). Even now during the Chaitra month festival (April - May) this massacre is celebrated in Madurai by a group of Hindus.