He was pronounced dead by ambulance officers when they arrived.
Campsie LAC Superintendent Michael McLean said police received “a number of calls” from witnesses about an altercation and when authorities arrived about 2.50pm they were faced with a “confronting” scene.
A 39-year-old Cabramatta man, who was arrested shortly after the fight, is believed to have been covered in blood.
It is not believed he was in any hurry, and was arrested as he sat calmly at Campsie Train Station.
“A male was seen on Campsie Railway Station and based on the description provided and physical evidence upon him we took the decision to make an arrest,” Superintendent McLean said.
The Campsie Commander said the attack was not random.
“I believe that at some point in time these people were known to each other,” he said.
A 16-year-old Canterbury Boys High School student, Findixon Sugiarto, student said he and a schoolmate were outside Campsie Library when the incident occurred.
“I heard screaming and then all I saw was the body and that’s when I got scared and went inside. I was about to call the ambulance but as soon as I picked up my phone I saw the cops.
“This doesn’t really occur in this area, this is normally a pretty chill pace — right in front of the church as well.”
Staff at Gloria Jean’s Coffees, which is on the second floor overlooking St John’s Anglican Church, said when the stabbing happened they heard screams from outside and everyone who was dining on the outdoor balcony moved inside.
Debi Saha, who was outside NAB Bank on the corner of Amy St and Beamish St, was shaken by the incident.
“I heard them arguing … a little bit of screaming. When that happened I ran to come to my house to check my son at that time I don’t care about anything, I only just have one son. “Every night here there is a problem … this area is bad.”