There was a sense of occasion about this ceremony of renewal at the austere red-brick towers of the Bronx River Houses in late August. A smiling Mayor Rudolph W. Giuliani, flanked by a retinue of officials, was on hand to help plant a tree, a symbol of the city's effort to give the embattled housing project a fresh start.
Officials call this crackdown on crime and graffiti Operation Commitment, and proudly proclaim it a model for the entire city. But one person not present that morning was Bronx River Houses' most famous native son, Afrika Bambaataa, an easygoing hulk of a man who is considered an originator of rap and hip-hop and who has recorded with the likes of James Brown and John Lydon, formerly of the Sex Pistols. He is still greeted with casual familiarity by his fellow residents, while fans from all over the world make this 44-year-old housing project in the West Farms section a place of pilgrimage because of him.
Mr. Bambaataa (pronounced bom-BAT-uh) would not have been especially welcome at the ceremonies for Operation Commitment this summer. That is because, in addition to being the progenitor of a musical-cultural style, he is also the father of a loose organization born 20-odd years ago at Bronx River, the Universal Zulu Nation. Mr. Bambaataa calls it a "hip-hop community" with members all over the world brought together by music and fellowship.
But police and housing officials say it is a gang, responsible for much of what was bad at Bronx River, which was a place where few walls were free of graffiti and where routine criminal activity -- drug dealing, robberies and shootings -- flourished. The Universal Zulu Nation has been expunged from the project, and officials say good riddance. In the spring, the group, which had met monthly at the project's community center since its inception, was barred from doing so. Colorful murals with the organization's name and logo, painted on the center's outside walls by one of the Bronx's best-known muralists and photographed by tourists, were removed.
At the project, there is anger over what happened to the group. And some residents see cultural insensitivity in a mayoral initiative that slapped down what some consider a local institution, no more threatening than any youth social club.
"The Zulus are like a quieting force," said Louis Andrus, president of the tenants association. "They quell a lot of things that are going around."
Still, police and housing officials say they have received numerous complaints in recent years about harassment of tenants by Zulu members. Ruben Franco, chairman of the city's housing authority, said some members had stopped and searched people at the project. Mr. Andrus acknowledged that some older people felt intimidated, understandably, in the mere presence of any large grouping of youths.
Mr. Franco said: "It was my decision they had to go. There was a general climate of disorder and hopelessness, and they were part of it."
Mr. Bambaataa himself is vague about his age, where he lives (he grew up at Bronx River, but says he now only stays at his "godbrother's" apartment there from time to time), and his given name. But he is emphatic that Zulu members are not a gang and have not harassed Bronx River residents. "I know that's a bunch of jive," he said. "If somebody got out of discipline, then we talk to these young adults and teach them respect."
Oddly, Mr. Franco and Mr. Bambaataa were both guests at a ceremony at the Bronx River community center last year for graffiti painters who had switched to canvas.
What is a gang, and does the Zulu Nation qualify? The ill feelings left by Operation Commitment stem from a clash on this question. To some inside and outside the project, the police, housing officials and the Mayor's office, unaware of Mr. Bambaataa's status in the musical world or his prestige among youth, have unfairly tarred his organization with the gang label.
To the city officials, getting rid of the Zulu Nation was essential to Operation Commitment's success. "They had made a mess of the whole place," said Walter Alicea, the Police Department's deputy commissioner for community affairs. So far, the whole operation looks good, they say. "This little experiment we're doing is showing great, promising signs," said Dennison Young Jr., Mayor Giuliani's counsel, in whose office the project was born.
Several officials explicitly connect the expulsion of the Zulus with what they say is a drop in crime at the project, which is home to 3,100 people in the West Farms area.
"In the five months since the graffiti and the Zulu Nation are gone, crime is down 52 percent and there seems to be a more upbeat feel to the development," John Hamill, the New York City Housing Authority's public information manager, wrote in a memorandum last month.
Though the police broadly ascribed criminal activity to the group, they could not connect it to specific crimes. Inspector Edward Delatorre, commander of the 43d Precinct, said he "couldn't say for sure" whether members had been arrested at Bronx River. Capt. Alan Powell, the ranking housing police officer there, said, "We never could actually link anything with the Zulu Nation as far as crime was concerned."
In his two and half years as manager of the projects, Gary Watt could not recall any members' having been arrested.
Mr. Andrus applauds Operation Commitment for making Bronx River seem cleaner and safer. Muggings in the hallways are no longer routine, and trash no longer blows down the pathways. A police trailer provides a 24-hour law enforcement presence on the grounds -- at least for now. Tenant patrols have been increased.
But Mr. Andrus questions whether the Zulus were part of the problem. After Mr. Franco announced his intention to bar the group, Mr. Andrus wrote a letter on its behalf, saying, "I have not once thought of them as a gang but more like a club being taught principles and pride."
Alexie Torres, who grew up in the same building as Mr. Bambaataa, said: "I would challenge anyone who calls them a gang. The Zulu Nation was the only organization in the community that organized young people."
Ms. Torres, director of Youth Ministries for Peace and Justice, which is based at a church across the street from the projects, said: "These people were targeted when indeed they could have been used as a resource. You took the only organization that was doing anything with young people and you literally isolated them."
In interviews with residents below age 40, there was near-unanimous support for the Zulus and for Mr. Bambaataa, universally referred to as Bam. Several youths, in their teens and 20's, said Mr. Bambaataa had taken them on tour with him.
"The Zulu Nation is suffering for its past," said Anthony Brown, a 37-year-old building maintenance contractor. "It was a gang, per se. Now it's pretty much a community organization. They help young people. Bambaataa is a scapegoat."
Sandra Johnson, 31, said Mr. Bambaataa was "trying to help the community, keep the kids out of trouble."
Dara Lee, 25, who was strolling through the project grounds with a friend, said: "I have the utmost respect for the brother. I've been to a couple of his meetings. He teaches not to go out robbing and stealing."
Several older residents, however, said the organization was mysterious to them, was perhaps a gang or a cult and was troubling because it seemed to function for some youths as a substitute family. None of the older residents admitted to having witnessed violence by members, but none wanted to be quoted by name.
Some of the group's literature, provided by by Mr. Bambaataa, denounces the idea that it is a "gang, hoodlums, stick-up artists," and includes advice to use condoms and warnings about saliva in the transmission of AIDS.
In the late 60's, Mr. Bambaataa was a proud member of one the Bronx's more violent street gangs, the Black Spades. "That was then, this is now," Mr. Bambaataa said affably. In the mid-1970's, as the gang culture was fading, he formed the Zulu Nation, which was organized at first primarily around break-dancers and rappers. It later graduated to be propagator of what Mr. Bambaataa calls his "universalist" philosophy. As enunciated in his characteristically diffuse style, it has a strong Afrocentric tinge, though Mr. Bambaataa said people of all races were in the group.
"We don't want knowledge saying Greece is the master of civilization, when a lot of the knowledge comes from Africa and Egypt," he said. "Jesus wasn't born on the . It's just a holiday. We take the truth from James Brown, from Farrakhan, from Sly and the Family Stone."
As he sat at an outdoor table in the project, residents continually walked up to greet him. Mildly, he expressed surprise that city officials had taken after his group. But the meetings have been moved for now, and the community center's walls are back to their original plain red brick. The police said Zulu members cooperated fully.
But the affair has not left their leader without feelings of anger and hurt. "We feel that Mr. Franco and Mr. Giuliani didn't do their research," Mr. Bambaataa said stiffly.
Photos: Afrika Bambaataa, a rap and hip-hop pioneer, is a prophetwithout official honor in the Bronx River Houses. City officials have barred a group he founded there, the Universal Zulu Nation, and have removed its murals, below. (Chester Higgins Jr./The New York Times; Photographs courtesy of Zulu Nation)