A boy, 17, has been arrested on suspicion of GBH by police investigating an assault on an Asda worker at the Tiptree store.
The teenager was arrested just before midnight on Sunday, and has been released on bail until August 6.
It follows the release of CCTV images, and officers still want to find two other men (pictured).
The supermarket worker was punched in the face when he asked a group of men to leave at 10,40pm on April 17.
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