A fourth person has been arrested over the death of a Tribesman gang member in Whangarei in October.
John Henry Harris, known as John Boy, was taken to the St John base in Kensington and died soon afterwards.
Police this morning arrested a 54-year-old man in Tinopai after carrying out simultaneous search warrants.
Last month, police made three arrests, with a 41-year-old man charged with murder and a 19-year-old man and a 21-year-old woman both charged with accessory after the fact to murder.
Police said the man arrested today will be charged but details were not yet known.