Israel Jack Rotorua police are treating as suspicious the death of Israel Jack, who was run over while walking home on Te Ngae Rd early on August 18.
They say at least two vehicles struck him as he lay on the road.
What is unknown is why he was lying there, how he managed to travel 1.4km in about five minutes during the last leg of his walk from town, and why his cap was found about 400m from where his body lay.
Detective Senior Sergeant Zane Smith said police were looking into suggestions that Mr Jack was picked up in a vehicle and might have been subjected to foul play before being left on the road.
"We are not going to just determine this was a road accident and move on. Mr Jack's family deserve to know what happened that morning and we will continue to dig until we find some satisfactory answers."
Mr Jack's family are mystified as to why he was walking home alone on the night he was killed.
An aunt of the 20-year-old, who asked not to be named, said he was nearly always surrounded by friends.
"He was really well-liked, he had a lot of friends and would hang out with his cousins, he just had people around him all the time and always came home with friends," she said. "He was a really good kid, he wasfocused on his work and on succeeding."
Mr Jack lived in Edgecumbe and had worked in the forestry industry for more than a year. He would travel to Rotorua for the weekends to meet his friends.
The focus of the inquiry remains on the stretch of Te Ngae Rd between the Caltex Service station at the Owhata Rd intersection and the McDonald's restaurant.
Police are particularly interested in information about any vehicles or people who stopped to speak to Mr Jack or picked him up.
They are also interested in details of any vehicles that were damaged on or about August 18, or vehicles that have had repairs or alterations to disguise damage.