Art All Night 'worked tirelessly' to prep security for all-night festival prior to shooting, they organization said More than 40 officers and private security were working the event when the shooting broke out.
An ominous warning posted on Facebook that a shooting might occur at the Art All Night festival in Trenton this past weekend did reach police officials before the gun battle that killed 1 and injured 29.
The post, made Saturday morning by Danielle Grady, a teacher in Hamilton, said: "Please. Please. Please. Do Not Go to the Art All Night. They will be shooting it up."
Mercer County Prosecutor Angelo Onofri said Thursday that his office learned Wednesday evening that a retired Hamilton police officer saw the post, and reported it to Trenton police at about 2 p.m. Saturday.
And Trenton Police Director Ernest Parrey Jr. said once the report was received, police commanders took it seriously.
After festival shooting, Trenton mayor-elect reintroduces firearm bill
"We acted immediately," Parrey said.
The police director said supervisors sent additional units to the festival, which was already well staffed with uniformed police and private security. "But we beefed it up," he said.
The department had obviously worked with the festival organizers ahead of time, with it being a high-profile, 24-hour event, he said.
"Our officers did a fantastic job, and they did their due diligence," Parrey said.
Onofri said earlier in the week, addressing the Facebook post, that people should call police if they have such information, instead of posting on social media.
In a statement Thursday, he said the investigation so far has found Grady believed her post would be viewed by multiple police officers who are among her Facebook friends.
And the post, the prosecutor said, was the reason that additional Trenton police responded, and were able to quell the incident so quickly.
"Without Grady's warning, additional deaths and injuries would likely have occurred," Onofri said in the statement.
LISTEN: 'I'm sorry did you say 7 victims?' EMS asks at festival shooting
Meanwhile, Art All Night organizers said Thursday they prepped a public safety plan for months and were working to shut down the event two hours before the gunfight started.
Lauren Otis, executive director at Artworks and one of the event's organizers, said a 14-person private security detail was working the event.
At 8 p.m. Saturday, the private security team was present, with four uniformed Trenton police officers and four Mercer County Sheriff's officers.
"In accordance with plans developed with the Mayor and Trenton Police, Police presence at the event would increase throughout the evening as deemed necessary by the Police," Otis wrote in a statement.
Around midnight, the statement said, the organization complied with a Trenton Police request to shut down outdoor activities.
Ultimately, they also complied with shutting down the event completely, and there were more than 40 law enforcement officers at the scene when the shooting broke out.
Otis said he and Event Director Joseph Kuzemka were on scene, working with police and security to disperse people and shut it down.
"The shooting that occurred at Art All Night is an unprecedented tragedy for the innocent victims and their families, for attendees, for the vibrant regional arts community, for Trenton, for New Jersey, for the nation," Otis wrote in the statement.
"We commend City of Trenton Police and other law enforcement on doing an incredible job containing a situation that without their presence could have been far worse."
- Kevin Shea contributed to this story
Paige Gross may be reached at pgross@njadvancemedia.com. Follow her at @By_paigegross Find NJ.com on Facebook.