If you can help police with any information, please get in touch on 105 and quote file number 200806/1185.
Police launched a homicide probe after the body was discovered about 7.30pm on Wednesday.
Detective Senior Sergeant William Loughrin said police would like to hear from anyone who saw vehicles speeding and/or following each other along Kopu-Hikuai Road last night, between 7pm and 7.40pm.
Locals have reported on social media hearing gunshots and of police cars travelling at speed down Paeroa Kopu Rd, south of Thames, shortly after 8pm.
Others reported they'd seen police cars driving along Hayward Rd in nearby Ngatea.
Waka Kotahi NZ Transport Agency has closed SH25A between Kopu and Hikuai in both directions due to the incident.
The highway was closed from 8.11pm and is expected to remain closed until late afternoon today.
Motorists were advised to take the detour route on SH25 through Coromandel or Whangamata.
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