"We don't believe we've identified the one we are looking for."
Mr Jackson said there hadn't been any other reports of similar suspicious activity.
He said they would like the men to come forward.
"We really don't know what their motives were."
The boys did the right thing by not engaging with them, he said.
Chair of the Martinborough Community Board, Lisa Cornelissen, said she had never heard of anything like it in Martinborough.
"People are aware and concerned."
Since the incident, the school community has been advising parents to remind their children about stranger danger.
CAN YOU HELP?
The driver is described as a skinny male of European descent with red hair, aged mid-20s to 30s, with some form of facial hair.
The passenger is a male Maori or Pacific Islander, aged 40 to 50, fat or solidly built, with longer dark hair. Both were wearing blue overalls with some kind of red tubing or piping down the side.
The vehicle is described as an older model white van with tinted rear windows and without hub caps.
People with information can call Mr Jackson on his direct line (06) 370 0306 or contact Crimestoppers on 0800 555 111.