Actor Michael K. Williams, who as the rogue robber of drug dealers Omar Little on The Wire created one of the most popular characters on US television in recent decades, has died.

Williams was found dead on Monday afternoon in his Brooklyn penthouse apartment, New York City police said.

He was 54.

His death was being investigated as a possible drug overdose.

Little, a "stick-up boy" based on real figures from Baltimore, was probably the most beloved character among the devoted fans of The Wire, the HBO show that ran from 2002 to 2008 and is re-watched constantly in streaming.

The Brooklyn-born Williams was also a ubiquitous character actor in other shows and films for more than two decades, including roles on the HBO series Boardwalk Empire and Lovecraft Country, and in the films 12 Years a Slave and Assassin's Creed.

As Little, he played a criminal with a strict moral code, known for taking advantage of a reputation for brutality that wasn't always real.

And he spoke many of the show's most memorable lines, including, "A man gotta have a code" and "All in the game yo, all in the game."

The character also broke TV ground as an openly gay man whose sexuality wasn't central to his role.

Williams appeared in all five seasons of The Wire from 2002 to 2008, his character growing in prominence with each season.

© PAA 2021

Hugh Jackman has paid tribute to his "extraordinary" father after his death.

The Greatest Showman star, 52, revealed his father Christopher died on Sunday, which was Father's Day in Australia.

He wrote on Twitter: "In the early hours of Father's Day (AU), my Dad peacefully passed away.

"And whilst there is deep sadness, I'm filled with such gratitude and love.

"My dad was, in a word, extraordinary.

"He devoted his life to his family, his work and his faith.

"I pray he's now at peace with God."

Jackman's parents moved to Australia from England as part of the Ten Pound Poms migration scheme in the 1960s.

He has previously revealed his mother left Australia and returned to England when he was a child, leaving his father to raise five children alone.

He has since reconciled with his mother and shared a photo of her on Instagram last month.

The Wolverine actor has praised him as a formative presence in his life, previously writing on Instagram: "Happy Father's Day to the man who taught me to show respect for others, for education, for being led by your passions.

"Who taught me to never stop growing and learning.

"To work hard and realise that preparation is the bedrock for success.

"And above all, to find purpose beyond oneself.

"I love you dad!"

© PAA 2021

Emergency service workers have described the moment a three-year-old boy who had been missing for three days flashed an unforgettable smile when he was finally located.

Anthony "AJ" Elfalak was reunited with his relieved family on Monday after being spotted by a rescue helicopter following a three-day search in rugged bushland.

Hunter Region Commander Simon Merrick said an SES volunteer walked up to AJ and put his hand on his shoulder.

"[AJ] turned to him with a massive smile on his face that he will not forget," Mr Merrick told reporters on Monday afternoon.

'It was an emotional moment.'

AJ, who has autism and is non-verbal, went missing from his family's remote rural property at Putty about 11.45am on Friday.

He was found sitting in a puddle drinking water from a creek bed by a rescue helicopter which directed ground search crews to his location.

The boy has been reunited with his family after surviving three nights alone in the bush in temperatures which dipped as low as three degrees.

Special Operations Team Paramedic Gerry Pyke said AJ's condition was "remarkable".

"He is a little survivor," Mr Pyke said.

"He had some lacerations on his lower legs... he did have a bit of nappy rash but he hadn't had a nappy change for a few days so we can't hold that against him."

Mr Pyke said once AJ woke up he was starving and ate three slices of pizza and a banana.

He will remain in hospital overnight for observation.

His father Anthony Elfalak said AJ had been bitten by ants and had fallen over but he is just grateful his son is alive.

"He's just clinging to mum," Mr Elfalak told TV crews.

"As soon as he heard his mum he opened his eyes and looked at her and fell asleep."

Footage broadcast by Nine showed the boy's family jumping around in jubilation when they heard he had been found.

"Thank you for everyone. Thank you for the government. Thank you for the police. Thank you very much," AJ's mother Kelly Elfalak told Nine News.

"Thank you to my friend, my cousin, my sisters, my family. Thank you, everybody and whoever prayed for us."

Anthony and Kelly Elfalak and their four sons moved to the property just months ago as Mr Elfalak's work as a plumber dried up amid the COVID-19 lockdown.

Over the weekend more than 130 people were involved in the search of the property and volunteers helped police on foot and on dirt bikes.

Divers also searched and drained a large dam on the property.

NSW State Emergency Services tweeted: "We are over the moon and very happy to have provided our assistance."

Family friend Alan Hashem, who was at the property when the boy went missing, spoke to Nine News after learning the boy had been found.

He said he had barely slept for days.

"We were driving ourselves crazy, this kid could barely walk," Mr Hashem said.

NSW Police Superintendent Tracy Chapman said investigations were ongoing into how the three-year-old ended up half a kilometre from his home.

"From a policing perspective we will still be continuing our inquiry to understand what has occurred over the past three days," she said.

"I know everyone has lots of questions."

The Elfalak family issued a statement late on Monday afternoon asking for space and expressing gratitude for everyone who assisted in the search for AJ.

"AJ is fine," the statement read. "Hold your kids close. Please give our family the privacy to appreciate what we have."

© AAP 2021

A three-year-old boy who went missing from his family's NSW Hunter Valley property has been reunited with his relieved family after being spotted by a rescue helicopter following a three-day search in rugged bushland.

Anthony "AJ" Elfalak, who has autism and is non-verbal, went missing from his family's remote rural property at Putty about 11.45am on Friday.

Police say he was found on a nearby riverbank by a rescue helicopter which directed ground search crews to his location.

He has been reunited with his family and is being assessed by NSW Ambulance paramedics.

The boy survived three nights alone in the bush in temperatures which dipped as low as three degrees.

His father Anthony Elfalak said AJ had been bitten by ants and had fallen over but he is just grateful his son is alive.

"He's just clinging to mum," Mr Elfalak told TV crews.

"As soon as he heard his mum he opened his eyes and looked at her and fell asleep."

Footage broadcast by Nine showed the boy's family jumping around in jubilation when they heard he had been found.

"Thank you for everyone. Thank you for the government. Thank you for the police. Thank you very much," AJ's mother Kelly Elfalak told Nine News.

"Thank you to my friend, my cousin, my sisters, my family. Thank you, everybody and whoever prayed for us."

Anthony and Kelly Elfalak and their four sons moved to the property just months ago as Mr Elfalak's work as a plumber dried up amid the COVID-19 lockdown.

Over the weekend more than 130 people were involved in the search of the property and volunteers helped police on foot and on dirt bikes.

Divers also searched and drained a large dam on the property.

NSW State Emergency Services tweeted: "We are over the moon and very happy to have provided our assistance."

Family friend Alan Hashem, who was at the property when the boy went missing, spoke to Nine News after learning the boy had been found.

He said he had barely slept for days.

"We were driving ourselves crazy, this kid could barely walk," Mr Hashem said.

Premier Gladys Berejiklian said she would be "absolutely delighted" if the then unconfirmed reports AJ had been found were true.

"I think all of us have been crossing everything to make sure AJ is brought back safely," she told reporters.

"And if that's the case, it's much-needed good news in otherwise difficult circumstances."

NSW Police will hold a press conference in Putty on Monday afternoon.

© AAP 2021