At 5.55am, the sole suspect in both incidents was arrested after returning to the scene on Marine Pde.
Kirk said the suspect was set to be interviewed later on Tuesday morning.
“We are providing support to the victims following this distressing incident. Thankfully, all three are recovering in hospital and are in a stable condition,” he said.
“We believe this is an isolated incident involving one offender only.”
Kirk said investigators will be making further enquiries to understand what occurred and why.
Scene examinations will be carried out on Tuesday, and public members will likely see an increased Police presence in the area and reassurance patrols across Wairoa.