Pukekohe police are bringing in a team of special investigators to step up efforts to identify the group responsible for arson attacks in the town.
Since October last year, there have been 30 suspicious fires attended by the Pukekohe Volunteer Fire Brigade.
On Monday, Detective Inspector Craig Bolton of the Counties Manukau police and his six-man investigative team were called into the area.
He said they were looking for a group of teenagers, aged between 15 and 18, who are believed to be responsible for the fires.
"[The fires] are definitely linked and it is the same group [starting them]," he said.
The suspicious fires started last year but it was their increased seriousness that has police most concerned.
"They have mostly been vegetation-type fires in parks and scorching of trees and bushes but it escalated in January this year to industrial bins - the bins outside the business that are for cardboard - and people's wheelie bins," he said. "When that happened, the reports started coming to the police."
Mr Bolton was investigating 14 of the fires.
"The most serious of the fires was the playground at Pukekohe Hill School," he said.
That fire, which was started in the early hours of January 28, caused extensive damage to the school's senior playground.
Mr Bolton's team have been busy over their first three days in the area and were tracing some strong leads. Yesterday, the team brought in five teenagers to the police station for questioning in relation to the fires.
He said they would be bringing in more people for questioning.
"We have got a lot of good information that has come in through the public and through the media that has generated a lot of good, positive talk," he said.
"We are hearing the same names over and over and the challenge for us is turning that talk into evidence to hold someone accountable."
But he said he does not believe the group were out to hurt people.
"There does not seem to be anything sinister to what they are doing at this stage," he said.
"For example, there was one industrial bin that was pulled away from the building and set alight so it shows there is a bit of thought put into it by the offenders and they are not just setting fire to a building because that is extremely serious."
- Waikato Times