"We also want to talk to anyone who saw a silver-coloured 2005 Peugeot station wagon in Ōakura at about that time, or may have noticed it travelling in the coastal area on that Friday evening," said Matuku.
"While we have arrested the two people we allege are directly involved in Jacob's death, we continue to piece together a timeline of Jacob's movements prior to his death," said Matuku.
Information can be given by contacting police on 105, quoting the file number 220731/0100.
Information can also be provided anonymously via Crime Stoppers on 0800 555 111 or online via www.crimestoppers-nz.org.