New potential evidence has emerged in the William Tyrrell case

New potential evidence has emerged in the William Tyrrell case, after police located another piece of material next to a creek at the dig site in Kendall.

The William Tyrrell search near Kendall less than 1km from where he was last seen. Picture: Peter Lorimer

Police hunting for William Tyrrell sent a piece of blue material off for testing on Friday as investigators continued to gather evidence in a bid to find the child’s remains.

The square piece of fabric was immediately packaged in a brown evidence bag after it was found by Strike Force Rosann officers, who have spent the past five days scouring bushland on the NSW mid-north coast where William went missing in 2014.

The cloth will be analysed in Sydney’s west, at the same lab that is testing two pieces of red string found by officers on Wednesday.

Both items are considered to be of interest to police, but testing could take weeks.

The new piece of evidence is the latest development in a renewed investigation that was launched by police on Monday, after new information regarding the boy’s disappearance came to light.

The area drawing police attention this week was an unassuming corner of land on Batar Creek Rd in the town of Kendall.

The site is 1km from William’s late foster grandmother’s home where he was last seen dressed in a Spider-Man suit.

A creek surrounding the site was drained over three hours on Friday, in the hopes of uncovering forensic evidence.

Meanwhile, about 30 riot squad officers in navy jumpsuits and bucket hats worked under a heavy canopy of gum trees, dressed in navy jumpsuits and bucket hats.

They were joined by plain-clothed forensic experts, a few members of the ambulance crew and some from the Rural Fire Service.

Officers were again assisted by hydrologist Jon Olley, who in 2011 helped police find the remains of Daniel Morcombe, the Queensland schoolboy murdered eight years earlier.

An excavator operated for hours at a time, pausing only ­occasionally for the officer operating the machinery to take a break.

Every day has been the same. The officers rake the dirt; shovel the dirt; sieve the dirt. Repeat.

Police at the scene of the William Tyrrell search near Kendall. Picture: Peter Lorimer

By Friday afternoon, the scene resembled an archaeological site – under the guidance of forensic grave archaeologist Tony Lowe.

The rising humidity eventually became too much for some officers, as they were forced to pour bottles of water over themselves to escape the heat. One cadaver dog, Tilly, was taken for a dip in the creek to cool down before returning to work.

Heavy rain is expected in Kendall over the next nine days, but police say they will continue to dig unless the conditions become dangerous.

The wild weather could extend the three-week search by several weeks, a NSW Police spokesman said.

Three large gazebos have been erected to cover tables where police sieve through dirt collected from around the site, searching for forensic evidence.

Black tarpaulins were extended over the ground to protect areas the police had already searched from becoming muddied.

Officers have also spent the week excavating the garden at the foster grandmother’s Benaroon Drive house, as investigators consider the possibility he fell to his death from a 5m-high balcony.

William’s foster parents were on Wednesday charged over the alleged assault of a child – not ­William – on Sydney’s upper north shore.

In a statement released on Wednesday, NSW Police said the couple were charged with common assault of a child who cannot be named for legal reasons.