TAIPEI (AFP) - Almost three weeks after a fireball engulfed hundreds of young partygoers in Taiwan, the death toll continues to rise with agonising slowness as parents keep vigil at their children's bedsides.

"She almost lost her heartbeat," said Michael Chu, father of 18-year-old student Julie, who suffered burns to more than 70 per cent of her body when the inferno scorched through the crowd at a water park on June 28.

"We kept calling her name, telling her not to be taken by the devil and that she had to live on bravely," Chu said.

Around 1,000 revellers had gathered for a "colour party" at the Formosa Fun Coast water park which turned into a nightmare when plumes of decorative corn starch being sprayed on the crowd ignited.

Horrific amateur footage showed crowds running for their lives, screaming as they were overtaken by flames.

The only parts of Julie's body that were spared were covered by her two-piece swimming costume.

She is often unconscious due to anaesthetics, and faces up to five more rounds of surgery to remove damaged skin, said Chu.

He added that doctors said it is hard to determine Julie's fate as every time they operate there is a life-threatening risk of infection.

And survival brings its own fears for her anguished parents.

"Her life is ruined. She can't go to school now and won't be able to have a career. She won't be able to get married," her father said.

"She has to face the rest of her life like this, to deal with it on her own when we're no longer around," he told AFP.

- 'She still has nightmares' -

Six victims have died so far, and there are fears the number will rise in what medics say is an unprecedented disaster for Taiwan, given the scale and severity of the injuries.

The first victim lived for two days with 90 per cent burns before dying. Since then, five more have succumbed to their injuries, the latest dying on Wednesday.

"We and many other hospitals are struggling to keep the severely injured alive," Chao You-chen, head of Taipei's Tzu Chi Hospital, told AFP.

"This is unseen before, so many people with such serious burns in one incident. The challenges have been huge."

Currently 387 people remain in hospital, with 199 in critical condition - 21 of whom have more than 80 per cent burns.

Most of the victims of the fire were between 18 and 25 years old.

Specialists from Japan have flown in to advise on the treatment of the seriously injured and Taiwan has undertaken the grisly, necessary task of importing metres of skin for grafts.

There is hope for one father whose 18-year-old daughter escaped with 55 per cent burns and is now stable in hospital.

"Her condition is better now but she still has nightmares," he told AFP, wanting to remain anonymous.

"She grips my hand until she falls asleep, asking me not to leave."

But even patients who are stable face months of treatment.

"We've got to make sure they don't get infected, that they have good skin graft operations, blood transfusions and sufficient nutrition," said Chao, whose hospital has mobilised 150 medical staff to care for the victims.

- 'He has a desire to live' -

The cause of the fire has yet to be determined, with authorities saying that either a cigarette or heat and sparks from stage lights could have been to blame.

The company that supplied the corn starch to event organisers Color Play Asia said it had warned of its flammability.

Three suspects have been released on bail as prosecutors investigate them on charges of offences against public safety and negligence causing deaths.

Owner of Color Play Asia, Lu Chung-chi, 41, was one of those bailed, along with hardware equipment technician Chiu Po-ming, 33, and special effects worker Liao Chun-ming, 39.

Six more are being investigated, Taipei prosecutors said, including both the chairman and the president of the water park.

Assets of the water park, Color Play Asia and the event's marketing company have been frozen, pending the criminal case, so that they can be used for compensation.

The government has promised to pay for all medical expenses while victims are in hospital, with the possibility of further support for rehabilitation as families face bills for long-term treatment.

As the agony continues for victims and their loved ones, heartbreaking life or death decisions are being made daily.

One young man, Huang Po-wei, 22, who suffered 95 per cent burns, opted this week to have his legs amputated from below the knees.

"He has a strong desire to live," said plastic surgeon Lin Huang-chi who is treating Huang.

"He knew if he did not (have the amputation) he would not survive."