Mr James said people walking the streets in the early hours were possibly up to no good and citizens should be vigilant in the Grove Rd, Sylvan Rd and St Aubyn St area.
Hastings mayor Lawrence Yule yesterday added his voice to the appeal for public help.
"People need to be extremely vigilant and need to report any suspicious activity to the police," he said.
"If they hear strange noises, or if anything is suspicious, they need to call police.
"Arsonists do ultimately get caught. The more the public help us the sooner police can put together a trail of evidence so we can we catch him, her or them."
"They have got away until now, but they won't eventually."
The arsons are endangering both lives and jobs.
The lastest fire was in an orchard owned by major apple producer The Yummy Fruit Company.
Director Paul Paynter said the lost toilet was an inconvenience, but if orchard infrastructure was targeted it would be a major blow.
"It is the height of the fruit season - we have probably three weeks of our harvest to go and more than 500 people on the payroll.
"It is a lot of money flowing into the community."
The region's harvest was "huge" and many orchards were stretched - short of pickers, bins and packing capacity.
"Many people are shoulder-to-the-wheel trying to get the job done and the last thing we need is some idiots looking for a Saturday-night laugh."
The number of arsons in the district have raised concern, with the most ominous arson involving a home invasion on March 13.
A family were asleep in their Jellicoe St home when a young man walked through the house, flicking a cigarette lighter at about 4.30am.
When challenged he left, but the family car was shortly set alight.
On two mornings separate fires were started less than two hours apart.
On March 15 a car was set alight in Alexandra St after a rag was pushed into its petrol tank and ignited at 3.38am. An hour later an unoccupied house in nearby Miller St was set alight, forcing the evacuation of the house next door which also caught fire.
On April 1 there was a fire at a classroom at St John's College, shortly followed by a truck at a property in the neighbouring suburb of Akina, the only fire outside the Parkvale/Mayfair area.
- Anyone with information should phone police on 06 873 0500 or 0800 555 111.
Heat trail
* Saturday, February 28, midnight: Relocated vacant house on a vacant section in Victoria St was set on fire
* Sunday, March 1: Fire destroys a relocated property on Hastings St.
* Friday, March 13, 5am: Vehicle set on fire outside a Jellicoe St house.
* Saturday, March 14, 4.25am: Car parked on Alexandra St set on fire.
* Saturday, March 14, 5.56am: Vacant house in Miller St set on fire, extensively damaged.
* Wednesday, April 1, 12.30am: Fire at a St John's College classroom.
* Wednesday, April 1, 2.03am: Truck set on fire in driveway of Buller St address.
* Sunday, April 5, 6am: Pirate ship at Splash Planet set on fire and destroyed.
* Sunday, April 12, 12.23am Parkvale School playground fire.
* Sunday, April 12, time unknown, trailer-mounted portable toilet in St Georges Bay Rd destroyed
