More serious charges are to be laid against a 16-year-old youth today in relation to the death of Wairoa man Barlow James Cooper, who died on Friday from a skull fracture after allegedly being struck in the head with a hammer.

Mr Cooper's body was found on Wairoa's River Parade on Friday night, the second violent death in the town in less than a week.

Following a post-mortem examination in Auckland yesterday, police said Mr Cooper, 35, had been struck with a hammer before his death.

Police later arrested two people, a 16-year-old youth and a 20-year-old man, and charged them with assault.

They both appeared in Gisborne Youth Court yesterday. The 20-year-old was remanded in custody to appear again on May 10, while the 16-year-old was remanded in custody to appear again today.

Gisborne police Detective Senior Sergeant Craig Scott said the 16-year-old would face more serious charges today, but would not reveal the exact nature of the charges.

Mr Scott said Mr Cooper's cause of death had been given as "a fracture of the skull resulting in an extra dural haemorrhage".

Police said they had recovered a hammer from a Wairoa address.

Mr Scott said police were still talking to people in the area at the time of the attack but were not seeking anyone else in connection with Mr Cooper's death.

Mr Cooper's death follows that of 25-year-old Jimmy King, who died at a party in Wairoa on April 24 of blood loss from a neck wound.

A 26-year-old Wairoa man was arrested and charged with assault in connection with Mr King's death.