It happened near the Al Oerter Recreation Center on Fowler Avenue around 3:17 p.m. on Tuesday.
In a maintenance building behind the Al Oerter Recreation Center, crime scene investigators gathered evidence of a fatal stabbing.
As families looked on, some of the children witnessed something they've never seen before.
Some of the children were nearby on a soccer field when the crime began to unfold.
The two parks workers were in the maintenance building, when all of a sudden people like Ashley Montes heard a commotion.
"What I heard was an argument," Montes said.
She heard a lot more than that, and so did several other people in the park at the time.
"I heard everyone yelling, 'He got a knife, he got a knife,'" Montes said.
The man who was killed was 31 years old and the suspect is 51 years old. The 31-year-old victim was stabbed in the chest and was taken to NY Hospital Queens where he was pronounced dead.
He left the scene of the stabbing but was later picked up in the park by police assigned to the U.S. Open.
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