A fire investigator has revealed at least two fires were lit in the grandstand of a Whangarei rugby league ground in addition to one which destroyed a nearby clubroom.

The two smaller fires at Jubilee Park were extinguished but the disused clubroom was razed after reports of a fire about midday on Saturday. After examining the charred remains fire investigator Michael Champtaloup said there were multiple ignition points, one in the clubroom and two at the nearby concrete grandstand.

He said the clubroom burnt quickly as the building was old, dry and well-ventilated. The Advocate also understands there were large quantities of paper and old filing materials inside.

"It was not secure and had been tampered with in the past. It was known as a bit of a "hang out" for people who shouldn't really be in there. It was [only] a matter of time before it would catch on fire," Mr Champtaloup said.


He said there were a number of witnesses to the early part of the blaze, which sparked more than 30 calls to emergency services.

Now police are calling on the public to help find those responsible. Police Detective Senior Sergeant Dene Begbie said he would like to hear from anyone who saw any unusual activity in the area around the Tarewa Drive park. He said no other offences were linked to the fire and was unsure whether the blaze was started by a group or someone acting alone.

Jubilee Park was owned by Whangarei City & District Rugby League but had not been used by the club since 2011.

Board member Sharon Bird said the field was used daily by a nearby school and another section of the park was leased to an educational trust.

The board was waiting for a fire investigation to be finished before any decision could be made on the future of the grounds, including the grandstand and changing rooms next to the burned-down club.

"Once we know what's happening with police and fire we'll sit down and work out what we're going to do in the future," she said.

Whangarei Fire Service senior station officer Corey Matchitt said crews had carried out "familiarisation training" in Jubilee Park as they suspected it was only a matter of time before there was a major event there.

• Anyone with information on the fire can contact Whangarei CIB on 430 4500 or call Crimestoppers anonymously on 0800 555 111.