Police have named the woman found in a burnt-out car in Havelock North as Ariki Rigby of Napier.
In a statement on Tuesday morning, police said their thoughts and sympathies are with the 18-year-old's family and wider Whānau and victim support will be offered to them.
Police said they were following a number of lines of enquiry in relation to Rigby's death, but urge the public to come forward if they have information.
"Anyone with information is asked to contact Police on 105 quoting file number 220905/1265. Information can be provided anonymously to Crime Stoppers on 0800 555 111."
An investigation was launched last week after the 18-year-old's body was found inside a car parked at Havelock North's River Road Recreational Reserve earlier this month.
Police originally "did not immediately identify that human remains were in the cabin of the car" because of the condition of the vehicle and instead thought the body was a sheep.
Two days later, a dog walker took a closer look at the vehicle and discovered the woman's body and alerted police to her findings.
Police then launched the investigation on September 5 into the "unexplained death".
