Police on Monday revealed how close they were to tracking down the man they believe scalded the infant in a "disgusting" attack in a Brisbane park.
Minutes after identifying the man accused of seriously injuring the nine-month-old, police discovered he had flown out of Australia just 12 hours earlier.
A manhunt for the alleged attacker has gone international after an arrest warrant was issued for a 33-year-old foreign national.
"It sounds like they were very, very close (to) catching him," the baby's mother told reporters on Monday.
"This obviously means that we're going to have to wait who knows how long to get justice for our son - it's a bit heartbreaking."
The man allegedly approached a family picnic at Hanlon Park, Stones Corner after midday on August 27, pouring a thermos of hot coffee on the infant's head before fleeing.
CCTV and enhanced images were released but it took five days for police to identify the man they believed was responsible for the "cowardly" incident.
The man was "aware of police methodologies" and had conducted "counter-surveillance activities", making the investigation quite complex.
"He was aware what we do to find people," Detective Inspector Paul Dalton said.
When they finally identified the man, the detectives' joy was short-lived.
"I was in the investigation centre when we put a name to the face and it was a very happy room, only for us to do a check in 15 minutes and find out we've lost him," Det Insp Dalton said.
"We've got 30 detectives working for me. They're devastated that they missed this person by 12 hours.
"I was deflated, but that deflation quickly turns into determination and resilience to get the job done."
Police obtained a warrant for the man's arrest for acts intending to cause grievous bodily harm, which carries a life sentence as a maximum penalty.
Det Insp Dalton said the man drove to NSW a day after the alleged attack before flying out of the country from Sydney on August 31.
The baby boy's mother said it was some relief that the alleged attacker was no longer in Australia.
"I had no idea where this person was, I didn't want to leave this hospital because it became our safe space," she said.Â
"Returning home I had panic attacks, and still continue to do so.
"I do feel relief that he's not in this country, in some sense, but I will always have fear and anxiety being out in public with my son - it's affected my mental health for the rest of my life."
The boy's father believed the police had done everything they could to find the man but the mother wanted answers.
"I just want to know why, why he did this," she said.
"These are questions that may always be unanswered."
'We will keep going until we find you': Detective Inspector Paul Dalton vowed to track down the man. (Jono Searle/AAP PHOTOS)
Det Insp Dalton said he was still scratching his head over a possible motive.
"There's not many investigations where you don't get a clear motive. It's strange," he said.
Police said the 33-year-old man had no family or criminal record in Australia and had worked in Queensland, NSW and Victoria.
He had either been on a working or a holiday visa since first coming to Australia in 2019.
Police will now work with international partners to find him.
"The AFP has already started inquiries in the relevant country, with relevant authorities," an Australian Federal Police statement said.
Police have been unable to locate the man since the attack. (HANDOUT/QUEENSLAND POLICE SERVICE)
Asked what his message to the man would be, Det Insp Dalton said: "We will keep going until we find you - I have not lost that determination."
The child has undergone multiple surgeries after suffering significant burns to his face, arms and legs.
The parents said their son was in good spirits but may take years to recover.
A GoFundMe page for the child has so far raised more than $150,000.
18°C