Related Clues:

• Like perennial rivals, constantly
• In a shouting match, perhaps
• Busily engaged
• On task
• Attacking the task
• A bird is busy
• Occupied in some way
• Occupied (in crime?)
• Fighting Italian army back first
• A flier up to no good
• A flighty creature up to some criminal activity
• An idiot committing a crime
• Going __: fighting
• Feudin' and a-fightin'
• "They're ___ again"