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Charlie Mason has spent the past few days tirelessly combing the banks of the Mahurangi River looking for his son Luke.
"I have walked these banks with the police and I have gone as far down as the riverbanks allow me before going out to the mangroves," said the grieving father as he gazed at the river's murky brown water yesterday afternoon.
Luke Mason's friends have also been walking the banks of the Warkworth river, anxious to help find their missing mate but not sure where to begin. They last saw the 17-year-old at a party on Friday night near Mahurangi College.
About 9.30pm, after drinking tequila, Luke got on his bike but never made the 30-minute ride home.
At 2am on Saturday some of his friends found his bike on a grassy bank next to the Mahurangi River Bridge on State Highway 1. It is not known why he stopped but his friends say he had drunk a fair bit. He may have been tired or needed a toilet stop but it is unlikely he would have wandered off without his bike.
"He's not the sort of person to leave his property lying around," said one of Luke's friends.
While the abandoned bike raised his friends' concern it wasn't until Saturday afternoon when he failed to turn up at their place that they really started to worry.
His mother and sister, who had arranged to meet Luke that morning, were also worried and contacted the police.
An unofficial search began for the farmhand who is described by his father as being "good natured" having a "good heart".
The police search and rescue team were called in on Sunday to assist in the search.
The teenager's bank accounts have not been used and his friends say his two cellphones are not working.
As time goes on without word, they fear he has fallen into the river.
Sergeant Dene Duthie said police had no clear idea what had happened to the teenager and were "looking at a whole range of scenarios".
There was nothing however to suggest foul play. Yesterday the National Dive Squad started searching 800m of river, while land-based teams worked through reserves, riverbanks and surrounding bush.
More than 18 police officers are involved in the search, which is expected to continue today.
Meanwhile Mr Mason is struggling to deal with what might have happened to his son.
"He's a good swimmer, he loved the water and it just doesn't seem right for him to fall [in]."
Mr Mason said Luke had only just started a new job as a farmhand, which he was thoroughly enjoying.
He said it was not in his nature to run away and he didn't seem troubled by anything.
"Luke was a good boy," Mr Mason said.
"He was good to his mum, good to me.
"I have walked these banks far too many times ... I just want to find him and put him to rest."
