Pecking on chicken

[Browniechicken]

My chickens are let out their coop to go around the year and forage - typically all 5 get along well they can eat with all their heads in one spot but recently anytime time one of the chickens is digging and looking for food next to the others two other chickens basically attack her. Is that normal or what should I do?

Now anytime she’s around the chickens she runs away as soon as they lift their head because she’s scared of being pecked

 

[rosemarythyme]

Is any damage being done? When she runs off, do they continue to pursue her or do they leave her be, since she's moved away?