An employment investigation is under way into the actions of police officers while they were deployed in Northland during Waitangi Day commemorations.
The investigation relates to allegations of inappropriate behaviour while the officers were off-duty on the evening of February 4 and the early hours of February 5.
The officers involved are not normally based in Northland. Police would not say how many staff were involved.
Earlier, police revealed a 28-year-old officer had been charged with indecent assault and sexual violation following two incidents in the early hours of February 5.
He appeared in the Auckland District Court on March 1 and was granted interim name suppression.
The charges arose from a complaint laid by another officer.
This week's announcement of an employment investigation is thought to be connected with the same incidents.
Assistant Police Commissioner Bill Searle said the New Zealand Police code of conduct applied at all times, regardless of whether staff were on or off-duty.
''Police treat any allegations relating to potential misconduct by police officers seriously,'' he said.
One of the officers had been stood down while enquiries were under way.
Searle said he could not comment further due to the ongoing employment investigation.