A man suffered a broken jaw in an assault outside a Tesco Express store.
The 23-year-old victim, from Broughton, near Preston, was punched to the ground in an unprovoked attack in Church Street, Preston at 1.40am on February 8.
He suffered a hairline fracture to his jaw and a cut to the bridge of his nose, which required three stitches, plus bruises and grazes.
The offender was described as stocky with cropped blonde hair.
Police want to speak to a man pictured on CCTV at the scene.
If you can help call Lancashire Police on 101, quoting crime reference DA1300485.
Alternatively call the independent charity Crimestoppers, anonymously, on 0800 555 111, or visit www.crimestoppers-uk.org.