Fanatics trained up a group of children from its stronghold in western parts of the city to fight against advancing Iraqi troops.
But two of the youngsters refused to carry out the twisted demands of their terror bosses.
The youngsters were severely punished for refusing to execute two prisoners in front of their families.
According to Iraqi News, they both had a hand chopped off by extremists.
Public amputations are a common punishment under the terror group's murderous regime, but the brutal punishment is normally reserved for people accused of theft.
ISIS leaders are resorting to increasingly desperate tactics as they continue to lose territory in Mosul.