A scheduled emergency exercise is underway at Rotorua Airport, involving several emergency services.

The exercise started at about 2.30pm and involves emergency services and airport stakeholders including New Zealand Police, St John, New Zealand Fire Service, Air New Zealand, Rotorua Airport staff and Rotorua Lakes Council.

A reporter at the scene said a bus was parked at the northern end of the runway which is being used as the mock "plane".

One fire truck is also on the runway.