A community has rallied around a devastated family mourning three young children killed in a house fire in Sydney's west.
Dean Heasman, 28, was today charged with three counts of murder, five counts of attempted murder and damaging property with intent to endanger life.
Police allege he lit a fire, barricaded seven children inside and prevented emergency services from rescuing them at the Lalor Park home early on Sunday morning.
Two boys, aged two and six, and a five-month-old girl were killed.
Four other children - three boys, aged four, seven and 11, and a nine-year-old girl - and their 29-year-old mother were rescued from the flames.
Tonight, dozens of community members attended a vigil to support the family and pay tribute the three children killed.
Fire and Rescue NSW Commissioner Jeremy Fewtrell was in attendance, saying the tragic incident had rocked firefighters who responded on Sunday.
"The incident of this nature had a very particular and a profound impact on our staff involved," he said.
"Events like this impact us on a personal, as well as a professional, level and it is a chance to gather with the community and share that experience with them."
Homicide Squad Detective Superintendent Daniel Doherty said police are investigating whether an argument may have led to Heasman allegedly locking the children inside a room and lighting a fire with an accelerant believed to be petrol.
"We'll allege that the doors had been locked and, as a result of that, prevented those inside, the occupants, to escape the fire," he said at a press conference today.
Their neighbour, Jarrod Hawkins, forced himself into the home and pulled three children and their mother out one-by-one while emergency services were on their way.
Doherty alleged police arrived and had to wrestle with Heasman to pull the 11-year-old boy from his grasp and rescue him.
The mother has since been discharged from hospital and is supporting her children as they recover in a stable condition.
Doherty alleged this was "one of the most violent acts that you can imagine".
He said police had received a call for a welfare check at the home late last month but, besides that, there were no indications of any issues.
"He has certainly no criminal history. There's no current AVOs," he said.
"It's quite unusual, however, as we just said before, so many times, these matters can go unreported."
Heasman, who remains at Westmead Hospital under police guard, appeared in court via a bedside hearing today after he woke from his induced coma last night.
He was refused bail and the matter has been adjourned to September 6.
Police are still investigating the fatal fire and combing through forensic evidence.
Detectives have spoken with the mother and her four children, who they will be working with to determine what has happened.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.
Support is available from the National Sexual Assault, Domestic Family Violence Counselling Service at 1800RESPECT (1800 737 732).
