The march included religious and community leaders and anti-violence groups, along with the Bronx District Attorney and police officials. Some of the marchers wore white to signify peace.
While overall crime in New York City is down, murders are up in the borough this year.
It was two months ago that three people were killed in the Castle Hill section, including an innocent bystander.
Detectives are searching for 51-year-old Sam Cross of the Bronx, who they say was captured on surveillance video fleeing the scene after the June 21 shooting in the parking lot of a strip mall on Castle Hill Avenue.
Police think it was gang related and that two of the victims were the intended targets.
But a third victim, 45 year old Arileida Jimenez, was an innocent victim who was in the wrong place at the wrong time.
"Three people gunned down at 9:30 in the morning is outrageous," said Bronx District Attorney Darcel Clark. "It was the first day of summer. People should be out enjoying the warm weather. There is a senior service center across the street. They had to be locked down inside. People had to run for their lives. No more of this."
The NYPD is offering a $10,000 reward for the man wanted in the case.
Marching 14 blocks in Bronx to scene of unsolved triple murder that killed innocent bystander. Disrupting traffic to get public to pay attention. Bronx DA here hoping renewed attention will generate tips. Cops say June 21 shooting at strip mall on Castle Hill Ave was gang related pic.twitter.com/1MWOkYM5jI— CeFaan Kim (@CeFaanKim) July 25, 2018
The silent peace march began at Watson and Castle Hill Avenue and continued 14 blocks to Randall Avenue, site of the June triple homicide. It was aimed at deliberately causing a traffic jam in the middle of the evening rush.
Organizers are hoping renewed attention to the case will help generate tips.
It was a silent march, but the message was loud and clear.
"I learn from my parents and it's just parents that teach their kid what to do," said 14-year-old Jason Castro of the NYPD Explorer program.
The program is for young people who aspire to fight crime, instead of getting lured into the world they say they see around them.
"Don't be with your friends who try to get you to do things that are bad," said Jason.
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