Police are appealing for witnesses.
An offender was seen brandishing a kitchen knife at around 11.35pm on Friday after an argument with a group of men.
It happened near to the pedestrian crossing in Wallingford Street.
The offender then ran away in the direction of Seesen Way.
A 21-year-old man from Wantage was arrested on suspicion of affray and possession of an offensive weapon. He has since been released under investigation.
Investigating officer, PC Alexander Scerri-Devonald, based at Wantage police station, said: “I am appealing for anyone who may have witnessed this incident to please come forward.
“Anyone with information can call the non-emergency number 101, quoting 43190245811 or make a report online.
“Alternatively, you can make an anonymous report to the independent charity Crimestoppers on 0800 555 111.”
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