A young Brisbane mum has told of the terrible moment she looked around and saw a stranger pour hot coffee on her nine-month-old son's head, minutes after laying out a park picnic rug.

In the chaotic scenes that followed, the screaming baby's skin began to blister as the alleged attacker fled with one of the woman's friends in pursuit.

The scalding of the child happened so fast, the mother says she barely got a look at the "strange man".

Police are hoping someone who knows the alleged attacker will recognise him from enhanced images they released on Thursday and come forward. Police released footage of the man after the “terrifying” incident at Hanlon Park, Stones Corner on Tuesday afternoon.

The boy's parents also issued a plea for someone to find the man who allegedly poured the Thermos of coffee on their boy.

The parents are still traumatised by the alleged attack after the child suffered burns to his face and chest, undergoing surgery.

He remains in hospital in a stable condition.

"Luckily (my son) is young and he probably won't remember any of this but we will and this is something we're going to have to carry forever," the mother said.

"I'm not even sure how I'm going to ever go to a park or anywhere with (my son) feeling safe again."

The mother said "some guy" poured hot coffee on him just 10 minutes after they had set up a midday picnic in the park with a friend and her baby.

She urged anyone with information to contact police, posting online: “This man needs to be found and charged”.

CCTV footage of the man police want to speak to over the attack on a baby in a Brisbane park. – AAP

The parents are still reeling from the attack, saying they can’t comprehend why someone would hurt an infant.

“I don’t know who would think that’s okay to harm an innocent little baby,” the mother said.

The mother said a nurse heard the baby’s screams and ran over to help before an ambulance arrived soon afterwards.

“It’s torture. I am supposed to be his protector and I couldn’t protect him,” the mother said.

“I’m just having flashbacks all the time about what happened.”

She said her friend ran after the alleged attacker but he got away.

A woman organising a GoFundMe page for the baby said she was the friend who was with the mother during the alleged attack.

The woman said she was sitting down with her own son at the picnic when she looked up and saw a “strange man” standing over the nine-month-old.

“This man ... poured a thermos of hot coffee over him. He (the baby) just started screaming,” she said.

The woman said she tried to pursue the “very fast” man as he fled but she tripped, returning to help her friend’s baby.

“Essentially all I could hear was his mum screaming 'it’s hot, it’s hot coffee’,” the woman said.

“We laid him down on the picnic rug and we peeled his clothes away, which revealed the peeling of his skin – his skin had started to blister.”

Police released two more images on Thursday after sharing CCTV footage of a man running from the park and down the street.

They said finding the man was critical to their investigation.

The man was wearing glasses, a shirt, shorts and a black hat.

He is believed to be aged around 30 to 40 with a "proportionate build and tanned skin".

Anyone with information is urged to contact police.