16/02/2017 3:06 PM AEDT | Updated 16/02/2017 6:06 PM AEDT

Grant Hackett Found Safe After Family Asked For Public Help To Find Missing Olympian

The retired swimmer reportedly contacted his father to let him know he was safe.

Jason Reed / Reuters
Grant Hackett has been found safe.

Troubled Olympic champion Grant Hackett has been found safe and well after he went missing for most of the day on Thursday, according to multiple sources.

Hackett's father Neville earlier declared the retired swimmer to be a missing person and made an emotional public plea to help find him. Hackett was arrested on Wednesday and released without charge after an incident at the family home.

Hackett was reported to be safe late Thursday, according to reports from Channel Seven, Channel Nine and Fairfax Media.

Earlier, Neville Hackett told reporters on the Gold Coast that his son was "mentally disturbed and needs urgent help".

"He's mentally disturbed and needs urgent help," Neville Hackett said.

Turning to address his son directly, Hackett's father said: "Grant, let us know where you are. We love you... and we want to help you."

Earlier it was reported that Hackett was being treated in hospital after his release from the Southport police station on Wednesday.It was reported Thursday that he had checked into a hotel and had not been seen since the morning, up until he was located late in the day.

Addressing reporters following the incident, Hackett's brother Craig said that he was a danger to both himself and the community.

"This is not Grant Hackett. This is a completely different person. I don't know who this person is. My mum and dad don't know this person.

"He's there in person but he's not there in mind, soul or spirit... we know people struggle to get mental health treatment these days [and] we're no different to anyone else. We're struggling to get that help.

"We're pleading for people to help us -- help Grant. Grant needs help."

Hackett's father, who was at home with his wife when his son "broke down", told the Gold Coast Bulletin that the 36-year-old had been drinking heavily.

"He was raving and ranting a bit," he said.

"He's big and powerful when he's not happy... We decided he needed some treatment but there was no way he was going to go so we called the police.

"No one was touched. No property was damaged... He didn't even make any threats but was not what you say is a 'normal person'."

Editor's Note: This story has been updated to report that Grant Hackett has been found safe.