Police responded to a report of an altercation involving a knife in Ninfield Road, Bexhill at 9.50pm on Saturday (17 July).
A 39-year-old man suffered a knife wound to the abdomen and was taken to hospital. He has since been discharged.
A 34-year-old man from Eastbourne was arrested on suspicion of causing grievous bodily harm with intent. He remains in hospital for treatment for an injury.
Anyone with information or who witnessed what happened is urged to report online or call 101, quoting 1508 of 17/06.