A 14-year-old girl has been arrested for her role in forcing a fistfight between two little Bronx girls, ages 6 and 7, that was seen in a disturbing YouTube video, authorities said yesterday.

Another 14-year-old girl and a 15-year-old were charged earlier in the case, and an older girl is being sought, the authorities said.

All face child-endangerment charges. The tiny fists flew on Jan. 3 at Poe Park in Fordham Manor as the older girls egged the fighters on.