The police are investigating a potentially fraudulent email, which has been presented as evidence at an inquest in Wellington.
The coroner, Ian Smith, has been looking into a mid-air collision over Paraparaumu in 2008, in which killed two trainee pilots and an instructor died.
On Thursday morning the family of David Fielding, the instructor who died, put the email before the coroner's court.
Sent to the family on Wednesday night, it was supposedly written by a senior manager at Massey University's aviation school, Frank Sharp.
The unsolicited email criticised the official crash investigation report and a manoeuvre being done by one of the trainees just before the crash.
Contacted by Radio New Zealand News on Thursday afternoon, Mr Sharp said he wasn't the author of the email and has no knowledge of its contents.
Mr Smith says the situation is an extraordinary development, and he has had no hesitation in calling in the police.
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