Gregory "Rabbit" Stewart chronicled killing after gangland killing on the streets of New Orleans, naming guns, shooters, vehicles and motives behind a litany of slayings as the admitted assassin began his turn on the witness stand Tuesday in the federal racketeering trial of 10 accused members of the "39'ers" gang.

Stewart, 25, is the government's star witness against his accused former associates in an alleged heroin-dealing conspiracy backed by frequent killings.

In his first day on the stand, Stewart was unabashed about admitting he orchestrated many of the murders that prosecutors have pinned on the group. He eagerly killed rivals as the gang's most prolific triggerman.

Stewart gave the jury of eight men and four women a tutorial in how to cut heroin to make it still seem pure, and in how to carefully skirt police while shedding blood in broad daylight on New Orleans streets.

Members of the gang sometimes rented cars or vans that served as murder vehicles, and they often shared guns, keeping several assault weapons in a cache they stored under houses, in alleys or hidden in grassy fields, Stewart testified.

They employed them frequently, he said.

"We was tight. We was really like a good team. We was unstoppable. We had the city on lock," Stewart said. "We used to go to the Young Jeezy concerts in Atlanta. I stayed in Mississippi right on the beach. We went to Miami for Memorial (Day) weekend every year."

And often, particularly in 2010 and 2011, they killed.

Stewart has provided federal authorities a trove of material for the prosecution of his former associates as he seeks to shave time off the four life prison terms he accepted as part of a 2014 federal plea deal.

In some cases, Assistant U.S. Attorney Myles Ranier acknowledged, his admissions have cleared rivals who were arrested for a few of the 16 killings identified in a 47-count federal indictment. In many more cases, however, he has implicated his former friends in addition to himself.

Prosecutors describe the 39'ers as a “hybrid” force of the Upper 9th Ward's G-Strip gang and 3NG, a notorious Central City drug clan named for its stronghold around Third and Galvez streets. Several of the alleged members also hailed from the Florida housing development.

Stewart, who said he started dealing drugs at age 11 and killed until he was caught in 2011, has admitted to a role in at least a dozen murders.

Among them was the December 2010 attack in New Orleans East that left bounce rapper Renatta "Magnolia Shorty" Lowe and Jerome "ManMan" Hampton dead in a car from a barrage of more than 50 bullets.

Stewart said the since-slain leader of the 39'ers, Merle Offray, ordered the hit on Hampton, who was associated with a group from the Calliope housing project. He said the word was out that Hampton planned to kill Offray for supplying heroin to 3NG.

"Merle said (Hampton) was gonna kill him. He said, 'Handle him,' " Stewart said.

So on Dec. 20, 2010, Stewart said, he and four others — Rico "Freaky" Jackson, Terrioues "T-Red" Owney, McCoy "Rat" Walker and Tyrone "Biscuit" Knockum — headed to the Georgetown Apartments, after failing to turn up Hampton in the Calliope area.

Stewart said he anticipated that Hampton was headed to the apartment complex to see Lowe.

Knockum drove the group in Stewart's white Ford Crown Victoria. Owney's girlfriend lived at the complex off Morrison Road, so he knew the gate code.

"We knew he was in the house by Magnolia Shorty. I'm like, 'We about to sit on that boy. Let's go to the gas station and get a cigar, and we gonna smoke some weed till he get out,' " Stewart said.

He said they paid someone outside a gas station to go in and buy the cigars, so they wouldn't be spotted on surveillance cameras. They waited by a speed bump in the parking lot of the apartment complex, so their targets would have to slow down.

"Rat shot first with the 9. He hit Magnolia Shorty. That's when the car crashed. Everybody went in their position, to go to their spot. T-Red and Freaky, they was at the back of the trunk by the back windshield. I was on top of the gate, shooting through the passenger door and the windshield and stuff, and Rat was on the side by the driver's side," Stewart said.

He estimated he fired at least 20 rounds from a .40-caliber handgun the group had dubbed "Barack."

On the drive home, Stewart said, he spotted another rival and considered killing him, but found that he and the others were too short on bullets, having spent most of them killing Lowe and Hampton.

"We shot until they was dead," Stewart said matter-of-factly of the double killing. Knockum and Jackson have pleaded guilty to their roles in the killings of Lowe and Hampton, and Knockum testified last week in a trial that may conclude next week.

Stewart also described a hit on Elton "Bo" Fields, one of three men who gunned down two 39'ers outside the Wing Shack on Desire Street on April 12, 2010.

The 39'ers lost three associates that day: Terrance "Cheddar Black" Butler, Derrick "Gucci Man" Jones and Jessie "G-Strip Baby" Terry.

The 39'ers dressed in black for Butler's funeral and in all white for Terry's service, Stewart said, often distinguishing between hard-core killers among the group and those less interested in gunplay.

"For Baby's funeral we had on all white, made sure everybody had all white, because Baby was an innocent person. He sold drugs, but he was a good dude," Stewart said.

"But Cheddar was like a gangster. He killed. He's just like all us. We had all black for him. That was the lifestyle he lived, and we wasn't tripping."

Stewart said he and Owney caught up with Fields, a member of a Desire housing complex gang, on Oct. 11, 2010, switching to a rented Dodge SUV before the attack on North Rocheblave Street in the 7th Ward.

Defendant Leroy Price drove. Stewart and Owney fired.

"(Fields) was parked, talking to a girl. We turned the corner, so me and Red hurried up and jumped out the car. I told the girl she better get the (expletive) out. She took out running. He tried to close the door. I slid in the door on him," Stewart said.

"I'm sitting on the door like this, hitting him in his face, and Red's (firing through) the back window, just hitting him like, until he died. ... I shot till my clip was almost empty."

Offray, who was later killed in 2013 at a bar across South Broad Street from New Orleans police headquarters, was happy with the deed, Stewart said, "because Merle loved Cheddar and he wanted everybody dead who had something to do with (his death)."

Stewart said he killed Calvin "Plucky" Celestine on Feb. 5, 2011 because Celestine "was playing games, two sides of the field" with Offray and Darryl "Breezy" Franklin, a 39'ers leader who testified earlier in the trial and is serving a life prison term.

"Breezy went to Texas with his money. He told me, by the time he come back, Plucky gotta' be dead," Stewart said.

He said he did the hit with a man named "Willy Bill," who is now deceased.

"I got heroin and money. I don't remember how much money. I think $9,000," Stewart said. "I went (and) splurged with it."

Ranier, the prosecutor, spent Tuesday afternoon walking Stewart through scores of wiretapped phone calls with some of the accused 39'ers, discussing drug transactions, lost weapons and efforts to skirt police and manipulate the justice system.

Among them was a series of calls in which Stewart said members of the 39'ers had spotted another rival, Corey "Co" Lewis, at a jewelry store in the Lakeside Mall and were scheming to kill him after he left. They failed, losing track of Lewis, Stewart testified.

Stewart, who is expected to spend several days on the stand, seemed to express more remorse over his lost friendships than over the killings he said he and others committed.

The loss of Owney as his running partner, he said, was particularly hard. He said he pushed to help Owney rise up and make money.

"With T-Red, bruh, that's really like my true brother. I know our relationship is over with, because, you know, what I'm doing to him right now," Stewart said as Owney sat at the long U-shaped defense table.

"If it come down to it, I really got love for them dudes. This is something messed up, that I'm really doing this. Like, life. I gotta' live with this," he said.

Stewart testified that he didn't hang out with defendant Damian "A.D." Barnes "all the way like that." He also said Alonzo "Woo-die" Peters "ain't no really violent person. He don't carry guns like how I say me and Red carry guns, me and Pound (Ashton Price)."

Stewart said Peters had to show up for the one murder he's named in: The Feb. 22, 2010 slaying of Kendall Faibvre, a Press Park gang associate, allegedly committed with co-defendants Ashton Price and Jasmine "Rell" Perry, along with Stewart.

It was a retaliatory killing for the shooting of a friend named Percy who became paralyzed, Stewart said.

He said he hatched the plan, called Peters and they positioned themselves around the target's house, "so we got the corners sewed up. He can't go anywhere."

"So when they pull off, that's when the shots came out. They went Woo-die's way. They stopped at the stop sign. When I pulled up behind him, Woo-Die and Rell got out, shot the car. I had a chopper too (AK-47). I know one thing: Pound 'bout to work him. Pound come out the car and hit the car with the chopper. I backed up and pulled off. We found out that dude was dead."

Stewart said he brought his personal AK-47, though the two assault weapons linked ballistically to the killing were not recovered.

Earlier Tuesday, Ranier presented Stewart with an AK-47, which he identified as his own, noting a flip switch added to boost its capacity.

An assault rifle used to kill Faibvre also was used in the April 12, 2010 killing of Quelton "Gutter" Broussard, a rival from the Desire projects who was gunned down in a car during a three-scene battle that claimed three 39'ers. Stewart admitted Tuesday to killing Broussard with Offray and Franklin.

"We had so many choppers," Stewart said, "so I don't really know."

Stewart said he went to see Percy, the paralyzed man, the day after Faibvre's murder.

"I told him, 'Son, we handled that. It wasn't the dude who shot you, it was one of his friends. They gonna' cry behind that,'" Stewart said.

"He (was) just like, 'Thank you.'"