Police were called to Pleasant Terrace in Holbeck at 11.37am yesterday following reports of a disturbance involving around six people.
A man found with serious injuries to his neck was taken to hospital, where he was said to be in a stable condition.
Four people - three women and one man - were arrested by police on suspicion of affray.
Also in crime: Man injured in suspected 'drive-by' shooting in ArmleyIn an update issued today, West Yorkshire Police said all four suspects had been released.
A 23-year-old woman and 32-year-old woman remain under investigation, while no further action will be taken against 47-year-old woman and 21-year-old man.
Anyone with information about the incident is asked to contact police on 101, quoting log number 724 of 02/08.