Western Bay of Plenty police Inspector Karl Wright-St Clair said police had received various reports over the past week of some sort of unusual odour at Mauao.
"It's farm land area but obviously we needed to discount the fact that it was either of the two missing people from this area."
Mr Wright-St Clair said police were unable to locate the source of the odour but were satisfied they had completed a thorough search of the area and "it's nothing untoward".
"The search for young Jack is suspended but we will actively work on any information we receive."
Earlier this morning police asked people to stay away from from area until at least midday, when they expected to re-open the popular walking tracks.
A reporter at the scene said many walkers had arrived at the closed track, stopping at the cordon before walking around it only to be turned back by security further up the path.
Police apologised for any inconvenience.