2 Kings 10:6-9

ISV(i) 6 But Jehu wrote them another letter: “If you’re loyal to me, and if you intend to obey my commands, then bring the heads of your master’s sons and meet me in Jezreel about this time tomorrow.”
Now the king’s sons, totaling 70 men, were living with the leading men of the city, who were their guardians. 7 When the letter from Jehu arrived, the city leaders arrested the king’s sons, slaughtered all 70 of them, put their heads in baskets, and sent them to Jehu at Jezreel.
8 When the messenger arrived to report to the king, he said, “They have brought the heads of the king’s sons.”
Jehu replied, “Put them in two piles at the entrance of the city gate until morning.” 9 The next morning, Jehu went out, stood still, and announced to all the people: “Are you righteous? I conspired against my master and killed him, but who slaughtered all of these?