Police began receiving calls about 9pm to say flares were spotted just off the Awatoto coastline.
One caller had seen one flare while a second caller said there had been three.
Search and Rescue was alerted and the coastguard quickly put to sea to begin a search of the area.
"We set up a search grid and used visual and radar - the radar is very accurate and can pick up something as small as a kayak within half a mile."
The first search was within half a nautical mile of shore but nothing was found.
The crew then carried out sweeps to about two nautical miles out but again nothing was found.
The only vessel in the area was a fishing trawler but it was far outside the zone where the flares were spotted.
Police said no one had been reported missing around the time.
Given the calm and relatively mild conditions there were initial suspicions the slow-falling parachute flares, which appear for about 30 seconds, may have been let off for someone's entertainment.
"But we have to go and check it out - we have to," Mr van Tuel said.
The volunteer crew got back to port just after midnight after the search was stood down.
The unwarranted discharge of emergency flares is an offence under the Maritime Transport Act.
The offence can carry carry a term of imprisonment of up to 12 months or a fine of up to $10,000 for an individual. A similar penalty applies to anyone making a hoax distress call.