A witness has come forward with crucial new evidence that could hold the key to solving the murder mystery of a young child who was found dumped beside a highway in South Australia.

The child's remains, believed to be a girl aged between two and four years old who died up to eight years ago, were discovered by a motorist on the Karoonda Highway, east of Adelaide, on July 14.

Now, an Adelaide business owner has told police how he recalls seeing a well-dressed man, aged in his 60s, emerging from scrubland along the highway in late May, according to The Australian.

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This weather-beaten suitcase (above) was dumped by the Karoonda Highway and laid there for weeks until a passer by stopped and inspected it, along with children's clothes scattered among the skeleton of a child

Superintendent Des Bray stood beside a fair-haired mannequin wearing a dark leotard and black tutu, similar to what was found with the young girl who was dumped beside a highway

The witness claims the clean-cut man donning a suit, appeared to be on the phone at the time before he disappeared on the other side of the 172km highway that links to Tailem Bend - a tiny railway siding township on the Murry River, about 120 km south-east of Adelaide.

The new tip-off of the possible suspect has led detectives to widen their search along the Karoonda Highway between Tailem Bend and Wynarka after the description of the man matched the statements by other witnesses, who also saw an elderly man during the same month.

In July, a South Australian police spokeswoman confirmed to Daily Mail Australia a search was underway for a man in his 60s carrying 'a dark-coloured suitcase' on April 13 and May 26.

Superintendent Des Bray said last month they have been trying to identify the 'mystery man' as it is 'very unusual' that nobody in the remote area seems to know who the 'older' man is.

'He is described as being aged about 60, of Caucasian appearance, average height, lightly built, clean cut and neatly dressed. He was not a local.' Detective Superintendent Bray said.

'We have no idea who that person is or why he might be there but they are credible sightings and we believe them.'

South Australian mounted police (pictured) search a remote outback location near Wynarka, a tiny railway siding township , for clues as to the skeletal remains of a murder girl which were found in a discarded suitcase wiht clothing dumped on the highway by a mysterious stranger and recovered six weeks ago

Detective Inspector Greg Hutchins examining a children's book near the dump site of the skeleton of murdered a girl whose remains were uncovered six weeks ago but whose identity still remains a mystery

It comes after detectives found a children's book at a lonely outback site during a search by mounted police patrols in the area where the skeletal remains were found almost six weeks ago.

During a search along the highway between Tailem Bend and Wynarka over the weekend, police found a book in the dirt.

This adds to another clue which emerged on Sunday, the positive identification of a soiled jacket found among 50 items of clothing, a faded suitcase and a degraded quilt with the child's remains.

A sharp-eyed shopper spotted an idenitical white embroidered and fur-trimmed girl's jacket listed by a NSW seller on eBay before alerting police.

The vendor has donated the new jacket to South Australia's Task Force Mallee set up to investigate the murder.

Police, who have yet to identify the girl, spoke this week about steps being taken in the investigation in order to find the name of the girl and identify her killer.

This soiled and degraded jacket was found among the clothing with the remains of the skeleton of a young girl found along a stretch of South Australian outback highway 120km east of Adelaide after a mystery man with 'an eerie presence' was seen carrying a suitcase along the road near the tiny town of Wynarka

A clothing seller has matched the little girl's jacket to this new embroidered and fur trimmed white jacket, (pictured) which they handed to the major crime unit task force which is trying to identify the girl who died violently at the age of between two ans four years about eight years ago

South Australian major crime squad Detective Inspector Greg Hutchins goes over the investigation into a child whose bones were found dumped in a suitcase in the South Australian bush

The murdered girl in the suitcase Found: On July 15 on the outback Karoonda Highway near Wynarka, 120km south-east of Adelaide Sighting: 60-year-old clean cut, well-dressed Caucasian man seen April-May carrying a suitcase on the remote highway The victim: • Believed to be a girl who died 'a violent and terrible death' • Aged 2.5-4 years at time of death • Likely Caucasian • Had fair hair, 18cm long • Was 90-95cm tall • Was killed at another location • Was killed some time since the start of 2007 Items found with the skeletal remains of the victim: White fur-trimmed coat, black sequinned tutu dress, pink slipper with butterfly motif, Dora the Explorer outfit, boxer shorts, patchwork quilt and a Lanza brand suitcase Advertisement

Starting 15km out of Wynarka, Mounted Operations police and major crime detectives searched in two teams travelling in different directions for any evidence relevant to the case.

Clues have been emerging in the month since police released images of the times found with the remains of a girl, who died 'a violent and terrible death'.

The murder mystery began when a well-dressed man carrying a suitcase was spotted by Wynarka resident Denise Edwards carrying a suitcase along the highway, which acts as a truck route between the South Australian grain belt and Port Adelaide.

Ms Edwards was walking her dog when she noticed the 'mystery man' between April 13 and May 26.

He was about 60 years old, of Caucasian appearance, average height, lightly built, clean cut and neatly dressed. She said he was 'really quite normal', but that it was odd he was there with a suitcase and he had 'an eerie presence'

Weeks later, a motorist passing the handful of houses at Wynarka picked up the battered suitcase and found a jawbone poking through the clothing.

Forensic police have determined the remains belonged to a Caucasian girl with long fair hair, 90-95cm tall who had died at another location.

Mystery clues: South Australian detectives released this collage of images of the labels and clothing, including the black boxer shorts (top right) found with the skeleton of the girl aged between 2 and 4 years old who died violently up to eight years before her remains dumped on a remote outback highway

This 'Sally ' clothing tag on the degraded items of clothing found with the dead girl is a Chinese brand which has also now been identified on clothing no longer readily available, but for sale on ebay

Members of the public have identified the 'Dymples' label as an ethical clothing label sold at Big W, and found a dress on ebay with the 'Sally' label.

In the suitcase with the little girl's skeleton was a pink Dora the Exlorer outfit and many less recogniseable brand items which are slowly being identified. Labels including 'Gaf', 'Miss X', 'HF' and 'Haolailh' have yet to be identified.

Satin boxer shorts have been matched to a boy's pyjama set still available on ebay.

The shorts belong to a 'Holden Commodore boys pyjama set' featuring the letters 'SS' and an image of a car across the front, which match a red t-shirt pyjama top bearing the same logo and picture.

The shorts and a dress with the brand name 'Sally' are vital clues police need to locate the family of the dead girl which one officer described as 'a little girl lost'.

Police have yet to identify the origin of this Gaf clothing tag (pictured), prompting excitement among online readers who believed they had matched it to a lael of children's clothing manufactured in the Sydney inner western suburb of St Peters up to 10 years ago

Gaf clothing was made by St Peters, NSW children's clothing manufacturer Eric Bersztyn, along with Misty and Billy the Kid labels, but Mr Bursztyn said the Gaf label on the item found with the murdered girl does not match the labels on his garments which were sold to Target, Best & less and Big W

One of the more recognisable items was a black Cotton On tutu, identified by Daily Mail Australia.

'We hope either a retailer or member of the public may be able to identify where the items have been or still are sold,' Major Crime officer-in-charge Detective Superintendent Des Bray said.

'The Dora the Explorer top is pretty individual and someone may remember this and remember seeing a little girl they once knew wearing it.'

One reader online suggested the number and variety of clothing items, which also had fabric or sewing imperfections, might suggest that a person connected with the girl might have sold seconds clothing at a market stall.

Do you recognise these? The H.F. label (above, left) and the Miss X brand bother appear to be Australian made and Det Supt Des Bray hopes that 'either a retailer or member of the public may be able to identify where the items have been or still are sold'

South Australian police commander Des Bray (above) addresses reporters near the outback town of Wynarka last month where the body of the young girl was found on a truck route between the SA grain belt and Port Adelaide

Late last month a group of mothers on the 'websleuths' online forum uncovered new clues in the case of the murdered 'suitcase girl' whose remains were dumped with a bag of children's clothing by the side of the road in a remote outback railway siding town.

In a discussion on a websleuths.com forum, the women have identified the distinctive tutu adorned with large sequins as a Cotton On brand dress for young girls which was discontinued several years ago.

The keen-eyed blog posters also identified the item originally described as a child's ruler as a Lanza brand luggage tag, probably from the faded bag in which the remains lay amid numerous items of clothing, and a patchwork quilt found in a degraded state as an 'I-spy' quilt.

When one woman blogger named Pheme on the websleuths.com online forum spotted this distinctive little girls' black tutu dress, she knew it was the same model as the one she had bought her daughter from Cotton On and that it had been made a few years ago

Pheme's discovery sparked Snoop Dog on the websleuth forum to track down this ebay image of the black tutu dress with its distinctive cross-stitched large sequins, which differ in colour to a few of the sequins on the found dress, perhaps because of the garment's degradation lying for weeks in the open on an outback road

Thought at first to be a child's ruler, the metallic object above was soon identified on websleuth.com as actually coming from a suitcase, which police then identified as a Lanza brand piece of luggage

An original Lanza brand suitcase (pictured) which SA police presented at a press conference about the continuing investigation into the murdered 'suitcase girl' dumped 120km south-east of Adelaide

When SA Police released this image of this badly degraded but colourful quilt found with the child's body, quilters quickly went to work identifying seven of the fabrics used in the hexagonal patches, including the 'musical note' material in the border which was sold at Spotlight fabric outlet some years ago