"I'm sure that people that are lighting those fires wouldn't like to have someone's life on their consciences."
Firefighters were tied up at the scene for about four hours. They were alerted to the fire just before 9pm, and finished up about 12.30.
"While we're out there, we can't be available to respond if someone had a housefire . . . it's not so long ago that we pulled someone out of a fire who would have perished if we'd been delayed five minutes. That can be the difference."
Mr Coneybeer said firefighters were "sure" the fires were deliberately lit.
A police dog brought in after another fire was lit behind the Duncan Pavilion on Rangiora Street around 10pm, but the dog lost the scent in the sand dunes, Mr Coneybeer said.
"It's obvious that someone's out there lighting them and it could've been really serious consequences if there'd been a bit of wind blowing.
"It took a lot of men and a lot of equipment because it was so spread out."
He asked people to be "vigilant" and call the fire service immediately if they saw smoke, or call police if they saw someone acting suspiciously.
Lighting fires was dangerous not only for people living nearby and for firefighters having to battle the blaze, but also for anyone walking among the sand dunes, as the fire could spread quickly.
Flames could be seen leaping into the sky from throughout Castlecliff, and smoke from the fires was seen from as far away as Aramoho and Durie Hill.