Kelly said that the 8th suspect, 23-year-old Elmer Confresi, turned himself into police Saturday afternoon.
A 9th suspect remains on the run.
He has been identified as 22-year-old Ruddy Vargas-Perez.
Police said on Friday that a street gang discovered one of their recruits was gay, so they attacked him, brutally beat and tortured him and two others.
Eight people ranging in age from 16 to 23 are being charged in the brutal attack on three gay men on Sunday.
Kelly says the three victims were held against their will by the assailants, while a fourth individual was beaten and robbed elsewhere in connection with the attacks.
The first of the related attacks occurred at approximately 3:30 a.m. Sunday, when a 17-year-old was approached by members of a street crew calling themselves the "Latin King Goonies." The teen was apparently an aspiring member of the group.
Kelly says the crew forced the 17-year-old into an unoccupied ground-floor apartment on Osborne Place, where he was thrown into a wall, made to strip naked, hit in the head with a beer can, cut with a box cutter and sodomized with the wooden handle of a plunger.
According to police, his tormentors denounced the victim and questioned him about his contact with a 30-year-old man who the same suspects would later assault. Afterwards, his assailants escorted him out of the location and warned him not to call police. At about 5:30 a.m., the victim walked into a nearby hospital and was treated and released. There, he explained his injuries by claiming he had been jumped by unknown assailants on the street.
Bronx detectives learned the victim's identity and questioned him, and he eventually told them the truth and that he hadn't revealed it because he feared for himself and his family.
Around 8:30 p.m. Sunday, a second 17-year-old who was known to members of the same street crew also was beaten and questioned about the same 30-year-old man, authorities said. This teen was robbed of his jewelry while being held against his will in the same apartment.
"These suspects employed terrible wolf-pack odds of nine-against-one, odds which revealed them as predators whose crimes were as cowardly as they were despicable," Kelly said.
Then, police say the 30-year-old man was lured there at 9:30 p.m. Sunday.
He was allegedly forced to strip to his underwear and then tied to a chair opposite from the teenager. The teenager, at the direction of his assailants, hit the older male several times in the face and burned him with a cigarette.
The suspects also hit the man with their fists and a chain, police said, and sodomized him with a small baseball bat. They forced him to consume 10 cans of the malt beverage "Four Loko" that he had with him.
One of the suspects said later the man was beaten for hours and then dumped outside of his home.
The victim was found unconscious at about 4 a.m. Monday on a landing in the building where he and his brother shared an apartment. He had no recollection of how he got there, and because of his ordeal, in which he was forced to consume so much alcohol, he was also unable to give a coherent account of what had transpired until Monday night.
The second 17-year-old victim, meanwhile, did not report the incident to police until late Tuesday. Like the other teen, he too withheld details of the assaults until he was re-interviewed by detectives on Wednesday.
At about 10:30 p.m. Sunday, Kelly said the older brother and roommate of the 30-year-old victim was at home in bed when five assailants let themselves into his apartment through the front door with keys taken from his brother.
The suspects pulled a blanket over his head, beat him and demanded money, police said. When he refused, the assailants placed a cell phone to his ear, on which he heard his younger brother tell him that he was being held against his will and to quote, "Give them the money." The older brother told his assailants where they could find $1,000 in cash in the apartment.
They reportedly stole the cash, a 52-inch television and two debits cards.
Kelly said the assailants left the apartment at 11 p.m., after tying up and gagging the victim using a combination of rope, clear plastic tape and blue painter's tape.
By 1:30 a.m. Monday morning, the victim managed to free himself and use a neighbor's phone to call 911. He initially told police only that he had been robbed, failing to reveal the facts involving his brother.
The assailants scrubbed the scene top-to-bottom with bleach, even repainting the walls to make it look new, police said.
"They could clean, but they couldn't hide," Kelly said.
Investigators said they still found alcohol cans and hair at the scene. And an onlooker slipped a phone number to detectives, leading them to the primary suspect. The victims, initially reluctant, also started to divulge more details about the assaults, Kelly said. The Hate Crimes Task Force took over the investigation, along with Bronx robbery and gang division and special victims squad and arrested the seven men.
Those arrested have been identified as Ildefonzo Mendez, 23; David Rivera, 21; Steven Caraballo,17; Denis Peitars, 17; Nelson Falu,17; Brian Cepeda,17; Elmer Confresi, 23; and Bryan Almonte, 17.
City Council Speaker Christine Quinn, the city's highest-ranking openly gay official, called the attacks "vile" and "horrifying."
"These attacks are appalling and are even more despicable because the victims were clearly targeted in acts of hate simply because they are gay," Quinn said. "The cowardly few who committed these crimes do not represent New Yorkers and our community will not be cowed by such violence."
Five members of the City Council visited the block Saturday where the street gang is accused of staging a string of torture assaults inside a vacant apartment.
Quinn passed out leaflets imploring residents to turn in the suspect still at large.
A weekend rally on anti-gay bias was planned following other crimes against gays.
On Sunday, a patron at the Stonewall Inn, a symbol of the gay rights movement since protests over a 1969 police raid there, was beaten in an anti-gay bias attack, according to prosecutors. Two suspects in the case were charged. Their attorneys say they're not guilty.
That attack followed the Sept. 22 death of a New Jersey college student, who jumped off the George Washington Bridge after his sexual encounter with a man in his dorm room was secretly streamed online. The student's roommate and another freshman have been charged with invasion of privacy. Authorities are considering bias-crime charges.