A probe into the actions of the NSW Police is now underway following a fatal incident that left one man dead and another critically injured after what is being described as a brawl. The tumultuous events unfolded in northern New South Wales, casting a spotlight on the suburb of Lismore.

On Friday morning, an unidentified individual brought a 31-year-old man, suffering from severe head trauma, to Lismore Base Hospital. His condition necessitated an immediate airlift to Gold Coast University Hospital, where medical professionals continue to fight for his recovery.

In a grim turn of events later that same morning, authorities discovered the lifeless body of a 25-year-old man on a walking track near Fischer Street in the Goonellabah area of Lismore. This discovery has added a somber note to the unfolding investigation.

Reports suggest that both men were embroiled in a physical altercation at Clifford Park earlier that day. The melee reportedly involved a group of 15 to 20 individuals, raising questions about the sequence of events that led to such a tragic outcome.

It is believed both men were involved in a brawl at Clifford Park in the suburb that morning alongside 15 to 20 other people.

A critical incident has been declared to analyse the response of police to the initial fight.

The investigation is being conducted by officers from the Mid North Coast Police District.

Police are looking for witnesses.