Chris Broad of the Emirates Elite Panel of ICC Match Referees imposed the fines after New Zealand was ruled to be one over short of its target, after time allowances were taken into consideration.
In accordance with the ICC Code of Conduct for Players and Player Support Personnel, and in particular the regulations contained therein governing minor over-rate offences, players are fined 10 per cent of their match fees for every over their side fails to bowl in the allotted time, with the captain fined double that amount.
As such, Kyle Mills was fined 20 per cent of his match fee while his team-mates received 10 per cent fines.
The offence is contrary to Article 2.5.1 of the Code. The penalty was accepted by New Zealand without contest so there was no need for a hearing.
The full text of the Code can be found here.