A NOTAM can be issued about any change to airspace, aerodromes or hazards that require immediate notification, according to Civil Aviation Authority documentation.
Rachel Meerkerk, who works at nearby Blue Pacific Minerals, said she had heard "a lot of sirens" in the area.
Emergency services at the scene of a plane crash in Tokoroa. Photo / Andrew Warner
Tokoroa Airfield is owned by the South Waikato District Council and is located at Amisfield, just south of Tokoroa township.
According to the council's website, the airfield comprises a grass runway 1120m long by 60m wide, including a sealed landing strip 850m long by 18m wide.
Aircraft up to 5700kg are permitted to use the runway. The civil aviation status is "non-certified" and "unattended".