Police say children at a Hamilton school were hugely upset when they saw the crosses they had put up for an Anzac tribute had been smashed up and ripped out overnight.
They said the crosses, which were laid in front of Berkley Intermediate School, were attacked by the intoxicated 17-year-old about 3am today.
Acting Detective Senior Sergeant Andrew Mortimore said there were about 40 crosses, and most of them had been pulled out or knocked over.
"They had taken great pride in the significance of this event, it being Anzac Day, and the learnings that they were able to do in the classroom about the war and the significance of these person's actions, the soldiers. They were certainly upset to learn firsthand and to see the result of this gentleman's actions."
Mr Mortimore said the police arrested the teenager this morning as a result of security camera footage from the school.