Police has arrested the 52-year-old female driver and charged her with two counts of unsafe driving.
Police confirmed the boys, both aged 8, suffered cardiac arrest and died in hospital after a female driver crashed her Toyota Kluger into a classroom at Banksia Road Primary School at Greenacre Tuesday morning.
The 52-year-old woman behind the wheel crashed into a demountable classroom that was occupied by a class of children and a teacher.
The vehicle was on the school grounds when the incident happened but police don't believe it was intentional.
About 9.45am (Tuesday 7 November 2017), emergency services were called to the school on Boronia Road, after a auto left the road and crashed into a classroom in which children were taught.
"He was saying "I want my mum".
Eyewitnesses reportedly told police that the woman appeared to have lost control while driving out of the school.
The ABC understands Ms Al-Shennag was a parent at the school.
'Obviously it was a scene of carnage, ' she said.
It was written by a year four student at the school.
"Once all people have been treated and assessed a total of five patients were transported to the Westmead Children's Hospital".
"Everything went blank", she said.
Her licence was suspended and she was granted conditional bail ahead of an appearance at Bankstown Local Court on November 29.
"You've got mothers over there fainting, you've got paramedics dealing with all the mothers and everyone is just nervous that it's their child".
Police are investigating how the crash happened, but NSW Police Commander Stuart Smith said: 'We do not believe this was an intentional act'.
'They were crying, they were distressed, some were asking for their parents.
"It is an active crash investigation".
"It is very, very hard because we are parents ourselves, we are human beings", she added.
NSW Premier Gladys Berejiklian, who visited the school on Tuesday afternoon, said her thoughts and prayers were with the victims after the tragic incident.
Following news of the incident, parents rushed to the school to collect children and check on their safety.