Three people have been charged with the murder of Lower Hutt man Matthew Stevens.
Mr Stevens' body was found alongside his car on the Paekakariki Hill Road on 29 November. He had been beaten and stabbed to death.
Detective Senior Sergeant Mike Sears said a man and a woman, both 27, had had their charges upgraded from previous accessory charges.
The third person was a 24-year-old man who was already in custody on unrelated charges, Mr Sears said.
All three would appear in the Hutt Valley District Court next Tuesday.
Mr Sears said all three were known to Mr Stevens and were connected to a property in Lower Hutt's Oxford Terrace which was the subject of an intensive forensic examination by the police.
"We've certainly got a lot of work to go but it's a huge milestone to be making three arrests today," he told Checkpoint.
"I want to thank the public for their assistance and willingness to come forward with information that has allowed us to piece together the events of that night," he said.
Mr Stevens family had been told of the charges.