Police will wind up their search for missing boy William Tyrrell in remote bushland and swamp on the NSW mid-north coast at the end of Wednesday.

Divers were sent to an area about 2km off a country road to scour a swamp, close to where search teams had been combing bushland just north of Bonny Hills.

The divers, from Sydney’s Marine Area Command, were searching Lake Innes, which feeds into a swamp.

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Detective Inspector Gary Jubelin from the Homicide Squad said the search would finish at the end of Wednesday as it had so far failed to uncover any evidence.

“At this stage we’ve recovered a number of items and property but at this stage we do not believe they are related to, or will help us, with the investigation into William Tyrrell’s disappearance,” he said.

Det Insp Jubelin said it was not unusual in a homicide case to find anything in a search.

“It’s only a minor setback,” he said.

Police divers search for the missing toddler at Bonny Hills on the mid-north NSW coast. Photo: NSW Police

He said the search was only one of many lines of inquiry the police were following up in the investigation.

William was last seen wearing a Spider-Man costume and playing in his grandmother’s front yard at Kendall, south of Port Macquarie, in September 2014.

A large-scale search that ensued failed to find any trace of the boy, and it is now thought he was abducted.

On Tuesday investigators said they had confidence in a tip-off received in recent weeks that led them to bushland in the Lake Innes Conservation Area.

The search area can only be accessed by four-wheel drive vehicles along a bush track.

Search crews are looking 3km on each side of that track in very thick bushland.

Detectives said the search was not their only line of inquiry and searches elsewhere would follow.

Police said they spoke to a number of people on Tuesday, although no-one was formally interviewed.

Officers also revisited the home of local tradesman William Spedding.

Mr Spedding, whose home was searched in January, denied any involvement in the case.

The search on Wednesday is expected to be the third and final day police will spend combing the area near Bonny Hills, which is about 20km from Kendall.

Police reiterated that they still wished to speak to anyone who was in the area when William disappeared.

“Anyone who was in the area at the time and who doesn’t come forward would cause us some concern,” Det Insp Jubelin said.