Detectives investigating the disappearance of three-year-old William Tyrrell believe he may have been abducted by a paedophile ring when he disappeared from his grandmother's house last September. Detective Superintendent Mick Willing, NSW Homicide Squad Commander, said on Friday: 'One of our lines of inquiry relates to people we expect to be involved in a paedophile ring.' He said detectives from the homicide squad and the sex crime squad are 'vigorously perusing that line of inquiry and this investigation is moving at a very fast pace.' 'We are perusing every lead that we get,' Detective Willing said. The news comes as the parents of the missing toddler have begged for his return in a heart-wrenching video made seven months after he vanished from his home on the NSW mid-north coast. 'Just give him back ... take him to a church, take him to a police station, take him to school. Give him to someone, give him back,' his mother says in a video released by police. The distraught couple has also released new pictures and home videos of the boy in the hope that new clues will emerge as to his whereabouts. Scroll down for video . New video: The parents of missing William Tyrrell, who police now say may have been kidnapped by a paedophile ring, released home videos of the missing son showing the lively young boy playing guitar (above) and playing around his home . Heartfelt plea: William Tyrrell's distraught parents released a video pleading for their missing son's return as well as home movies showing the lively boy riding his bike (pictured) and playing at the family home . Full of life: The new videos of William Tyrrell (pictured, above at a slightly younger age) show a smiling boy full of energy and his mother has begged kidnappers to show her son care and love if the little boy is still alive, seven months after police believe he was abducted from his grandmother's NSW mid north coast home . The parents of missing three-year-old William Tyrrell have released new pictures of their son and a video pleading for his return by abductors who are believed to have snatched him in daylight last September . 'Just give him back':  The parents (pictured) issued the plea in an emotional video released by NSW Police to encourage people to come with forward with new leads as to the missing toddler's whereabouts . In the videos, William can be seen riding his bike down a path and flashing a cheeky grin, as well as playing a guitar and swivelling his hips in times to the music. William was last seen dressed in a Spider-Man suit and playing in his grandmother's yard in broad daylight in a quiet street in Kendall last September. Investigators believe he was snatched during a very short window of time when he was out of sight of his family as he played outside. Legal restrictions have prevented William's parents from speaking publicly throughout the ordeal, and their identities are not revealed in the video. The home videos of William were released on Friday. William's father choked back tears as he remembered his son, who was infatuated with the Spider-Man superhero. '(He loved) anything that related to Spider-Man and superheroes,' William's father said in the video. 'He's a cheeky, vibrant little boy ... full of energy. I mean he's my little boy.' But he said William was a cautious boy who wouldn't go with a stranger. Vigorous pursuit: NSW Homicide squad boss Detective Superintendent Mick Willing (pictured) revealed on Friday that police are investigating William Tyrrell's disappearance at a very fast pace and that 'one of our lines of inquiry relates to people we expect to be involved in a paedophile ring' One of the new photos released by police of William Tyrrell show the three-year-old smiling and drawing, while other images and photos show an energetic and happy youngster full of life . A new home video of cheeky William Tyrrell (pictured, eating cake) has been provided by the family in their desperate wait for the return of the three-year-old, seven months after his probable kidnap . William's father (pictured in a videoed plea filmed by NSW Police) choked back tears as he remembered his son, describing the toddler's love of superheroes . Homicide Squad Commander, Detective Superintendent Mick Willing talks to the media in relation to the investigation of missing toddler, William Tyrrell . His mother said she had a vision that somebody 'reached over ... has gone `clump' on his shoulders, picked him up and moved him on ... because ... that's the only way ... to explain for him not to be there.' She said the family was struggling with not knowing where William is or what happened to him. 'We need to know what happened to him ... `cause we can't live forever ... like this.' She said she hoped whoever had him was looking after him. 'I want him to be safe, I want him to be feeling loved and I want someone to be looking after him because to imagine that something else is going on ... we can't live like that.' William was playing in his grandmother's yard dressed in a Spider-Man suit in Kendall, on the NSW Mid North Coast last September when he disappeared in broad daylight . William Tyrrell's parents released this new photo (above) of their missing son, with an impassioned plea in which his mother said she had a vision that somebody 'reached over ... and has gone "clump" on his shoulders' William's mother said in a tearful plea that she hoped whoever had her son (pictured) was looking after him and making him feel loved . The parents are calling for any who has any information to contact Crime Stoppers immediately on 1800 333 000. The release of the video comes more than a month since police scoured bushland in Bonny Hills, south of Port Macquarie, for evidence relating to William's whereabouts. Police divers were brought in from Sydney to search a murky dam in a bush reserve and a nearby swamp, after more than 30 officers and the dog squad had spent spent two days searching through dense bushland - including along a track that can only be accessed by four-wheel drive. The release of the video of William (pictured) comes more than a month since police scoured bushland in Bonny Hills on the NSW Mid North Coast in a renewed effort to find the boy who vanished last September . NSW Police divers search a dam for evidence of missing boy William Tyrrell near Bonny Hills, NSW . Police divers were brought in from Sydney to search the murky dam in a bush reserve, and a nearby swamp . The three-day search was carried out near local washing machine repairman William 'Bill' Spedding's home. Mr Spedding was identified as a person of interest in the case after he was due to fix William's grandmother's washing machine around the time the toddler vanished. However, Mr Spedding says he didn't go to the house on September 12 because he couldn't get in contact with William's grandmother. Police searched the 63-year-old's home and business in nearby Laurieton in January, seizing various items, including cars, a mattress and computer, for forensic examination. Mr Spedding has strongly denied any involvement and police have previously stressed he isn't their only line of inquiry.
Police revealed they are 'vigorously perusing' paedophile ring theory.
Parents of  William Tyrrell have released a plea for his safe return.
'We can't live like this,' mother said as search entered its seventh month.
Police say search of NSW bushland is reaching the conclusion stage.
Divers were brought in to search a murky dam in a bush reserve.
William Tyrrell vanished from his home in Kendall, NSW in September 2014.