Residents say a fire at the public toilets near Northland's Ocean Beach on Tuesday morning threatened human lives, multiple buildings and native bush.
The bathrooms off Ranui Rd below the Whāngārei Heads Surf Club (WHSLSP) have been completely gutted by the fire.
Lifeguards staying at the club alerted emergency services through their radio rescue network at around 3:40am, as the local phone lines and power were out.
"It looks purposefully lit," WHSLSP club captain Julian Pitman says.
"Luckily we've had a quite a bit of rain over here the last few days and nothing else caught fire."
Police and Fire and Emergency NZ have been investigating, and the local campsite has been closed due to the lack of facilities.
Wendy Newbold lives up the hill from the fire and says if it wasn't for the 11 millimetres of rain that fell on Monday, the fire could have been disastrous.
"The toilet block backs onto a very old pine forest which has been tinder dry until recently.
"If it hadn't rained it would have been all over for us, the surf club and the walking tracks along Bream Head."
"The toilets would have been really difficult to actually burn. They must have used an accelerant of some sort so it was obviously planned.
"It's a crazy thing to do. It's not just an act of vandalism but it was potentially life endangering.
"I hope they catch the buggers."