Four men were taken to hospital after following a street fight in the Llanrumney area of Cardiff.
Police were called to reports of men fighting in the street in the early hours of Sunday at Countersbury Avenue.
It is believed weapons, including possibly a small axe, were used.
Three men were arrested in relation to the incident.
Two men, aged 18 and 19, arrested on suspicion of affray have been released on conditional bail, while a 31-year-old arrested on suspicion of assault has been released under investigation.
The four wounded men were taken to University Hospital of Wales where one man is recovering from surgery. The others have since been discharged.
Officers have been carrying out a search of the area and house to house enquiries as part of the on-going investigation.