Residents in a Waikato town are having their sleep disturbed by midnight explosions.
Mystery surrounds what could be causing the noise waking many residents of Cambridge.
Like many on her street, Maria had been recently woken at night by explosive noises. She likened the sound to someone trying to blow a hole in a mountain.
When her neighbour woke to the noise, he worried Cambridge's old river bridge had collapsed, but despite many people sharing their experience online, so far there's been no explanation.
The explosive noise, which has been heard more than once, so disturbed Terry McDonnell, he wrote a letter to the local Cambridge newspaper, looking for answers.
"You'll just be asleep and then, in the middle of the night, it's like a bomb, a really loud bomb," he said.
McDonnell had heard it in the night three times and said each time it's happened has been unsettling.
"The first time, I thought, 'Oh my God, has someone died?' and you wait for the sirens, all the ambulances - but nothing."
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He ruled out the sound coming from a car backfiring or fireworks, or even gunfire.
Wife Jo McDonnell agreed it wasn't the usual bangs and crashes people might hear living in an urban area.
"It's just really loud, it wakes you up... like a bomb," she said.
Across the road, Jasmine also felt the sound was beyond the everyday and found it quite scary in the middle of the night.
"I thought a war was starting," she said, when asked to describe the noise.
She was so shaken by it, she couldn't get back to sleep for hours.
Along the street, Alison just wanted answers to what caused the reverberating boom.
"You are fully awake and fully alert," she said of its effect.
Like Terry McDonnell, she said it was a sound she expected to bring emergency vehicles rushing out.
"You think something major has happened, but there's no follow-up sirens," she said.
Police told RNZ they were not aware of any calls for service relating to the noise and it was not a police matter.
Waipa District Council said it also hadn't had any complaints or inquiries.
Both organisations turned down requests for interviews about what the noise could be.
Terry McDonnell said many people in Cambridge reported being disturbed by the noise and he hoped someone would come forward with an explanation.
"Someone must know," he said.
In the meantime, the neighbourhood must go to bed, wondering whether they'll get a quiet night's sleep.
