Chickens heads ripped off... In an enclosed space! - HELP PLEASE!

[ChickenBoii]

Hello, my chickens died in a 100% enclosed cage... Here is the design:
A chainlink fence going 3 ft in the ground and 2 above. A door but its not 'easy' to get in.
But.... What's been happening is strange it's just a hole throught the chickens, usually where the head was...
Please Help

Also I live in CA (California).

Ontop is a tarp but they're no ways a raccoon could've got in unless it was a VERY small one.

 

[ChickenBoii]

Also, just found some evidence that a Chicken escaped with its feathers arround neck GONE...

 

[ChickenBoii]

Only the black chicken's seem to survive

 

[bobbi-j]

A weasel can easily get in through a chain link fence. They have been known to eat chickens' heads.

 

[enola]

Is the tarp the only thing across the to of the run?

 

[centrarchid]

Chain link fence? Work on showing pictures of setup and carcasses. I would not rule out predator doing business from outside just yet.

 

[sourland]

If a chicken can escape, something as large can get in. The possibilities are myriad. Is there a coop that can be locked?