GRANT Hackett’s father says his son was found by police “alive and sober” and “very, very embarrassed” but the Olympian won’t yet say where.

Hackett’s family reported him missing after the “mentally disturbed” Olympic champion’s violent arrest and dramatic meltdown at his parents’ Mermaid Waters home on Wednesday.

Nev Hackett said his son had texted his mother Margaret to say he was ‘okay’.

“He was located by police as a result of the media blitz,” Mr Hackett said.

“He is alive and sober and very, very embarrassed.

“He’s not talking to anybody. I have the police with me now and we’re learning more about what happened.”

Police are refusing to provide further details, citing privacy reasons.

media_camera Grant Hackett posted a picture facial injuries to Instagram today. Picture: Instagram

EARLIER: GRANT Hackett’s father has reported his “mentally disturbed” son officially missing.

Nev Hackett said he had contacted police and appealed for anybody who knows where Grant is to advise urgently.

“He’s definitely a missing person and he’s definitely mentally disturbed,” Mr Hackett said.

He said Grant, who was arrested at the family’s Mermaid Waters home on Wednesday after a violent meltdown, was last seen at the Versace hotel early Thursday morning.

Mr Hackett said he phoned his son and asked “Where are you?” but Grant immediately hung up.

“He’s missed two appointments this morning, one with his doctor and the other with his barrister,” he said.

“We’re extremely worried.

“My best guess is that he’s in a hotel room somewhere because his phone’s switched on but he’s not answering.”

Mr Hackett dismissed reports that Hackett had checked himself into hospital.

EARLIER: Grant Hackett’s father says he doesn’t know where his son is following his dramatic arrest yesterday.

Speaking briefly to media at the family’s Gold Coast home, Nev Hackett, who called police on his son, said: “I don’t know where he is.”

Mr Hackett declined to comment further, saying: “Every time I say something he gets upset.”

He would not be drawn on social media claims by Grant earlier today that a family member ‘beat the s ... t out of me’.

In the post, he made unsubstantiated allegations that his brother Craig “is an angry man” who “beat” him.

It’s not clear when the photograph was taken but the 36-year-old did not appear to be carrying the facial injuries when he was arrested on Wednesday.

“My brother comments to the media ... but does anyone know he beat the sh*t out of me. Everyone knows he is an angry man,” Hackett wrote on Thursday morning.

Yesterday Grant’s distraught family said he had sunk from Olympic swimming champion who “had the world at his feet” to a raging “danger to the community” they didn’t even know any more.

Hackett was last night believed to be in hospital after a dramatic day in which he was arrested at his family’s Gold Coast home when he flew into a violent rage in the latest in a spate of shocking meltdowns.

His former senior police officer father was forced to call police on his “raving and ranting” son, who is “big and powerful when he’s not happy”.

Hackett was reportedly “going off” and stabbing a knife into a chopping block before his family reported it as a domestic violence incident to police.

Eight police officers arrived at the Hackett’s home at Mermaid Waters and took him into custody in handcuffs.

He was kept in Southport watch-house for several hours before being released without charge, and was later believed to have been taken to a Gold Coast private hospital.

Hackett emerged looking dazed and bleary-eyed from behind bars to say he was “not great” and would be seeking more treatment “in due course” for what his family described as “mental health issues”.

media_camera Grant Hackett's father Nev outside his Gold Coast home. Picture: Nigel Hallett

Hackett’s older brother Craig said the former superstar swimmer was now a stranger to them.

“This is not Grant Hackett, this is a completely different person,” he said.

“He’s there in person but he’s not there in mind, soul or spirit ... and it’s to the point now where at times, he’s dangerous.

“He’s a danger to himself, he’s a danger to the community and his poor mum and dad have tried to look after him so much.

“I’m concerned for their welfare. We’ve reached the end of the road. He had the world at his feet ... such a role model to so many kids ... and now no one knows what’s going to happen. It doesn’t look encouraging.”

Hackett’s father Nev said his son had become “abusive and aggressive and wasn’t making any sense”.

“No one was touched, no property was damaged, he was raving and ranting a bit but ... he didn’t even make any threats but was not what you say is a normal person,” he said.

“It’s what I’d call a bit of a breakdown. Eventually I had to call the police and they settled him down.”

Mr Hackett said he thought his son was affected by alcohol at the time.

“Alcohol, and I suspect there could be prescription drugs as well,” he said.

media_camera Grant Hackett leaving the Southport Watchhouse yesterday. Picture: Jerad Williams

“We decided he needed some treatment but there was no way he was going to go and get treatment this morning so we called the police.

“The only way the police can do anything under the law of the land is to arrest him for domestic violence.’’

After leaving the watch-house, Hackett said he missed his family. Asked if he would seek more rehab, he said: “I think I need to.”

Yesterday’s incident is the latest in a spate of meltdowns involving the increasingly erratic Olympian.

Hackett entered rehab in 2012 for addiction to the powerful prescription drug Stilnox, and underwent treatment again in 2014 after he was found wandering semi-naked around Melbourne’s Crown casino claiming to have lost his son.

It followed an ugly divorce from singer Candice Alley and the alleged trashing of their Melbourne apartment.

Last April, he was involved in a midair scandal when he allegedly “forcefully” tweaked the nipple of a fellow passenger on board a Virgin flight between Adelaide and Melbourne after the man reclined his seat.

After that incident, Hackett — who has worked as a senior banker with Westpac and as a Channel 9 commentator — said “binge drinking is an issue that I need to address and something I will address”.

Nev and Craig Hackett said their son and brother desperately needed help.

“If he gets the right type of treatment ... maybe, just maybe, he might be able to claw himself out of it,” Craig said. “He does have days where he is fantastic, but unfortunately those days are becoming few and far between.” Nev said: “Grant’s got a long road ahead of him but we will support him the whole way.”