Siblings have been left shattered after their brother was allegedly stabbed to death by a man who had absconded from a mental health facility.

Setefano Mooniai Leaaetoa, 25, allegedly stabbed three people at shops on Merrylands Road in Merrylands, in Sydney’s west, about 10am on Tuesday.

Amamuddin Sadar, 38, died at the scene, while a 47-year-old woman and a 21-year-old man remain in hospital.

Sadar’s siblings told 7NEWS of their unbearable grief and shock.

“Deep pain that we cannot express the way it hurts,” his sister Meena said.

The family said Sadar moved to Australia from Afghanistan 15 years ago in search of a better life.

“He was a very, very honest and compassionate person towards everyone,” his brother Masoud said.

A former housemate paid tribute on social media, describing Sadar as “incredibly hardworking”.

“We didn’t interact much, but we’d always exchange a simple greeting, and he seemed very sincere,” the housemate said.

The family are now seeking answers and government assistance to allow relatives overseas to travel to Australia to say goodbye.

“We’d love to bury him with our own hand,” Meena said.

NSW Health confirmed Leaaetoa fled authorities on February 7 while being transferred between Cumberland Hospital and Westmead Hospital’s emergency department, two days after he was admitted.

He has been charged with murder along with two counts of causing grievous bodily harm with intent to murder and will remain behind bars until at least May 13.

Just a day after his escape, another man, 31-year-old Luke Francis, allegedly absconded from the same facility after overpowering a nurse and stealing her access pass.

Francis allegedly stole a car, leading police on an hour-long pursuit before colliding with another car at the intersection of Remembrance Drive and the Old Hume Highway south of Camden on Saturday.

Two women — 60-year-old Lee Casuscelli and 84-year-old Maureen Crosland — died at the scene.

NSW Premier Chris Minns said the state’s mental health system “has gone badly wrong”.

“NSW Health is treating more people with psychiatric illnesses… than ever before and the vast majority of those cases end up with the community (being kept) safe, the individual getting help that they need,” he said.

“But this one has gone badly wrong, and we need to make sure that we’re learning the lessons from it.”

NSW Nurses and Midwives’ Association Cumberland branch president Nick Howson, who works at the hospital, said the mental health system was “broken”.

“There’s not enough people to go around, either security, nursing or medical,” he said.

“I was dragged over a wall by a very large individual and I ended up in a hospital bed on spinal precautions.”

Another nurse, Teaghanne Sarina, described a similar experience.

“Kicked me in the chest and broke three of my ribs. I was alone in this situation because it was just two nurses to six patients,” Sarina said.

Cumberland Hospital is one of the country’s largest mental health facilities, dealing with the community’s most troubled and sometimes violent patients.

Major changes are now being demanded to better protect staff, patients and the wider community.