From the Annals of the Oasis Kingdoms:
In the 115th year, the son and heir of the King of Niya was leading a patrol along the oasis trade roads when he was killed in a dispute with soldiers of the Green Banner Army. In retaliation for the loss of his son’s head, King Badal Parsu decreed that fifty of the soldiers of the Green Banner Army should lose their heads also, displayed above the main gate of Niya. This decree was carried out.