An allegedly fatal stabbing of a father has been described by police as “absolutely senseless”.

Two teenage boys will front court on Monday charged with murder over the alleged attack of the 36-year-old man on Cleeve Cl in Mt Druitt, Western Sydney, about 9pm on Friday.

WATCH THE VIDEO ABOVE: Sydney teens charged with alleged murder of tradesman

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Police will allege a 13-year-old boy stabbed the man in the torso twice, killing him.

Superintendent Darrin Batchelor said initial investigations suggest the altercation “seems to be a chance meeting that was totally innocent”.

“What we have learnt so far from our investigation is the 36-year-old male was on his way home, he’s employed in the local area, and was speaking to a number of young people that he knew through family and friends,” Batchelor said.

“Another group of young people took offence to that conversation that that 36-year-old male was having with those young people.”

A family has allegedly been town apart after a ‘family man’ was allegedly stabbed to death by a teenage boy in Western Sydney on Friday night. Credit: 7NEWS

Investigations also suggest the man had offered to give his family friends some money to make sure they got home.

CCTV footage from the scene soon after shows the man running from several people before being tackled to the ground.

That same footage captured first responders and paramedics desperately trying to save his life.

“We now have that male, who is a family man with children, is now dead,” Batchelor said.

“In my 30-year career of policing, I find this absolutely senseless.

“I have no doubt The impact of the community and the victim’s family will go on and on for years.”

Family torn apart by alleged murder

Batchelor added the man’s family “is obviously distraught”.

“A family has lost a father, a son, a brother and now they will have to live a future without their father,” he said.

“He was there doing a good deed to help young people get home.”

Police will allege the altercation broke out ‘by chance’ before the 36-year-old was allegedly set upon and stabbed twice in the torso. Credit: 7NEWS

He added the teenager is known to police, with detectives recognising and tracking him down over the weekend. He was arrested at Mt Druitt Police Station about 7.20pm on Sunday and charged with murder, breach of bail and an unrelated robbery offence.

About 40 minutes later, a 16-year-old boy was arrested at a home in Cabramatta and charged with accessory after the fact to murder.

Police will allege the charge stems from a knife being found in a drain outside of a unit block in the same suburb.

“Although it still has to be forensically tested, we are confident that that was the knife that was used in the offence,” Batchelor said.

Both boys will appear before a children’s court on Monday while police launch a manhunt for others allegedly involved in the attack.

“There’s more arrests to come,” Batchelor said.

“There are two individuals who we know who they are. we know their names, we know where they live.

“So for those two individuals who we know, I suggest they hand themselves in to police as soon as possible.”