Detectives investigating an assault in East Preston have arrested three people.
Officers responded to a report of two men assaulting a man during an altercation in Sea Road about 4pm on Thursday (15 April).
The victim - a 20-year-old man - suffered a stab wound to the abdomen and was airlifted to hospital. He was subsequently discharged.
A 20-year-old man from Angmering was arrested on suspicion of causing grievous bodily harm with intent and possession of a bladed article in a public place. He has been released on bail pending further enquiries.
A 16-year-old local boy was arrested on suspicion of causing grievous bodily harm with intent and has been bailed while enquiries continue.
A 37-year-old local woman was arrested on suspicion of assisting an offender and has been released under investigation.
Detective Inspector Kim May said: "These arrests represent significant developments in our investigation as we continue to work hard to establish the circumstances.
"We continue to appeal to anyone who saw what happened or witnessed any suspicious behaviour in the area.
"We understand that this incident may have caused concern and would like to assure the public that we are investigating this as a priority and we will not tolerate violence in our communities.
"This incident is being treated as isolated and there is nothing to suggest that there is any threat to the wider community."
Anyone with any information, or who witnessed anything suspicious, can report it online or call 101, quoting Operation Treble.
Worthing's "Hardest Geezer" run's with the Prime Minister
Antique clock returned to Brighton museum following 2001 theft
Sussex Clare’s Law statistics
Liphook woman to row 8000 miles across the Pacific Ocean.
Sussex specialist domestic abuse courts introduced
Appeal to reunite owners with suspected stolen silverware
Plants to spend £26million on West Sussex County Council Computer System
Two men jailed in Crawley murder investigation
Those in Sussex with learning disabilities at risk of heart disease
WANTED: Connor Davis, 29, from Hayling Island
On Air