"Where's our cousin?" yelled someone in a mob of men rioting at the entrance to Landguard Bluff on Monday.
Others waved signs, one saying "Go home", while more men grabbed sticks and whacked them against the wall of shields in front of them. Some threw rocks.
"You're right next to your brothers, stay strong," Private Ryan Van de Pas said after the "riot", which was an exercise for the army's First Battalion Royal New Zealand Infantry Regiment.
The soldiers have been taking part in various role-playing exercises, some more intense than others.
Private Van de Pas said when the "rioters" start throwing eggs, "your blood starts to boil".
"You just really want to hit them," he said.
It could be worrying if heavier items were thrown, but he took comfort in standing alongside his fellow soldiers.
He enjoyed the exercises, saying it was good having "a bit of brutality".
"You get to have a bit of a laugh about it at the end."
Monday's exercise involved a scenario in a fictional country, Bekara, where unrest had broken out between their army and police.
The New Zealand army had been sent over to help stop the outbreak of a civil war, Major Chris Shaw said.
The mob of men were cousins to a man, Ryan Jose, who was killed during a military operation the day before, and another cousin, Eytan Jose, had gone missing. It was suspected the NZ army detained Eytan for questioning.
Major Shaw said Whanganui was a great place to hold the exercises as there was a variety of locations and terrains.
The exercises covered a range of scenarios, including one where a "known enemy" was at Ravensdown Mill "planning on defending the location".
"Our guys are tasked with destroying," he said.
Another scenario near the wharf was a similar situation, but the enemy was unarmed.
The exercises would focus on getting the soldiers to apply the "correct tactics".
Major Shaw said they were "trying to really drill into the guys the importance of responding to a threat" without "outright aggression".
They needed to focus on averting violence, he said.
Captain Andy Bedford said they were also looking at "shortened response time", where the soldiers had to react to a situation they didn't foresee.
Major Shaw said the exercises were "invaluable".
They will be holding them for the next few days.