Perhaps the most famous mass murder in the New Testament is Herod the Great's slaughter of children a short time after Christ's birth (Matthew 2). Herod was a cruel man who had a giant ego and a willingness to do whatever it took to maintain his authority. Herod took great interest in the Magi, and the mass of people who accompanied them, when they stated they were seeking a child born "King of the Jews" (Matthew 2:2).
According to the New Testament, however, He soon grew "exceedingly angry" (verse 16) with them when they failed to tell him the exact location of the Christ child. His anger, coupled with his desire to protect his throne, led him to order the mass murder of all male children, two years old or younger, in and AROUND Bethlehem. This cruel act secured his place as one of the most evil humans in the New Testament.
In a reference found only once in the New Testament (Luke 13:1), the Bible gives us brief details regarding a mass murder commanded by Pontius Pilate. This act is mentioned when Jesus is asked what he thought about Pilate's extermination of some Galileans as they gathered to offer animal sacrifices...
He, as Rome's Prefect over Judea, was known for committing acts of murder.