NEWARK, N.J. (AP)  -- Mounds of dirt dot the playground where three college-bound friends were gunned down and a fourth gravely wounded a year ago, symbol of a transformation that will wipe away most of the physical remnants of the horrific events of Aug. 4, 2007.

As the one-year anniversary approaches, the lingering effects of the grisly crime also can be gauged by the numerous anti-crime measures it spawned and by the unprecedented philanthropic outpouring that followed.

``Out of that tragedy came collective action and a collective will to get things done,'' Mayor Cory A. Booker said last week.

On a larger scale, the slayings of Iofemi Hightower, Terrance Aeriel and Dashon Harvey were no less a defining moment for Newark than the riots that engulfed the city 40 years earlier.

Yet the similarities end there; while some of the resentments from 1967 endure, the flood of national and international publicity generated by the schoolyard killings had a galvanizing effect and spurred a series of reforms aimed at preventing similar tragedies.

Clement Price, a historian at the Newark campus of Rutgers University and a longtime resident, sees the transformation of the Mount Vernon School playground, driven by the city's existing relationship with the Trust for Public Land, as an example of a new civic mind-set.

``What turned out to be a killing field has turned into a green space,'' he said. ``That would not have happened in Newark 20 years ago, where you would use the power of tragedy and intersect it with the power of commemoration.''

The slayings thrust Newark and its 38-year-old mayor into the spotlight almost immediately after the bodies were discovered late on a Saturday night.

As Terrance Aeriel's sister, Natasha, clung to life with knife and bullet wounds to her head, Booker became the target of local critics who blamed him for the city's high homicide rate.

The city seemed on the verge of splitting apart until James Harvey stepped onto a podium at a news conference and used his son's death to make a plea to all parents to ``raise your kids better.''

``It was almost like a balloon deflating, where you could feel the divisiveness just draining out of the room,'' Booker recalled.

Within two weeks, six suspects had been arrested, including an illegal immigrant, 28-year-old Jose Carranza, who was out on bail at the time of the killings despite facing separate assault and child rape charges.

The outcry over Carranza led to a revamping of bail policies for illegal immigrants. Other changes followed, including the instituting of penalties for gun owners who fail to report lost or stolen weapons, and a first-of-its-kind agreement to allow all New Jersey municipalities access to a federal gun-tracing database.

The killings also jump-started a project to put surveillance cameras in high-crime neighborhoods in Newark. About $2 million was raised in the weeks after the killings, and the first cameras were in place by September. More than 100 had been installed by the end of June, and police have credited them with cutting down on violent crime.

By the midpoint of 2008, homicides were down by more than one-third in a city where killings had risen by 50 percent earlier in the decade.

``Measuring the effect of that incident on what's been happening in the city is something that's going to be open to speculation,'' Police Director Garry F. McCarthy said. ``But there's certainly been a palpable change in this city.''

All six suspects have been jailed since their arrests. The three suspects who are juveniles will be tried as adults.

Last month, the families of the victims filed a lawsuit against the Newark school district that claimed the Mount Vernon school failed to provide adequate security in a rear courtyard where the victims were killed. Booker declined to comment when asked about the lawsuit.

Natasha Aeriel lives in an undisclosed location and is in good spirits despite the serious wounds she suffered, according to her father, Troy Bradshaw. She underwent two surgeries _ one lasting 14 hours _ immediately after the attacks and still cannot hear out of her left ear or move the left side of her face, according to the lawsuit.

The Street Warriors, a community anti-violence organization, has scheduled a rally on the steps of City Hall on Aug. 2 commemorating the lives of Hightower, Harvey and the Aeriels as well as other victims of violence in Newark, including 18-year-old Sujeiti Ocasio, who was slain on the day she graduated from high school last month.

Booker said last week he was still weighing how to mark the one-year anniversary of the schoolyard killings, though he said he would probably spend the Saturday night on one of his regular late-night police patrols in some of Newark's toughest neighborhoods.

``The best way to honor their memories is to keep showing as a community that we can pull together and reduce the violence,'' he said.

1010 WINS Boroughs & 'Burbs: New Jersey