4 week old chicks one eye

[RoyalHen]

are swelling, turning black and the eye appears to be protruding. It is odd to me and we have never seen this before. The one is dead and now we have a second one doing the same.

Can anyone tell me what may be causing this?

 

[CoopCrazy]

Do you know if they were ever on a plane ( i.e. shipped eggs or chicks) ??? Pressure can cause that , i have heard that it can affect shipped eggs as well..