NEW YORK — Victor Woods shook uncontrollably, his body wracked by convulsions, as fellow inmates held him in their arms and shouted for help.

Amid the chaos inside a Rikers Island dormitory, surveillance video showed a lone figure of relative calm: a guard watching it all unfold as he sipped coffee.

“I’m not touching him,” the guard was quoted by inmates as saying.

Within hours, Woods, a 53-year-old unemployed tunnel worker who had been arrested a week before on heroin possession charges, was dead. What exactly killed him remains under investigation, as are inmate claims that guards and medical workers took up to 20 minutes to respond.

Woods was the seventh inmate to die in 2014 at Rikers, a sprawling complex of lockups built on an old waste dump near LaGuardia Airport where this year startling disclosures of guard misconduct, inmate beatings and the gruesome deaths of inmate after inmate have slipped from behind the barbed wire.

In March, The Associated Press began detailing dozens of deaths – from a homeless ex-Marine who essentially baked to death in a hot cell to a mentally ill man who sexually mutilated himself. In other cases, procedures meant to prevent suicides weren’t followed.City, state and federal authorities responded to those and other news reports with oversight hearings, investigations and a pledge of millions toward overhaul.

Yet Woods died at the height of all this scrutiny.. His case is one more sign that the problems on Rikers Island – decades in the making – may take just as long to correct.

“There’s no silver bullet for fixing Rikers,” said Martin Horn, the commissioner of city jails from 2003 to 2009. “I always say running a jail is like growing a garden. If you turn your back on it, the weeds take over.”

Mere miles from New York City’s skyscrapers, Rikers Island sits by itself in the East River, a 10-jail facility where an average of 11,000 inmates a night – men, women and youth – are held on charges ranging from trespassing to murder.

Inside, inmates sleep side-by-side out in the open or in other, more restrictive individual cinderblock cells. The halls are filled with a pungent mix of odors from sewage backups and cigarette smoke.

“It’s a world on its own there,” said Marcell Neal, who was released in October after spending 35 days on a parole violation.

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It is also a world where violence reigns and both guards and gangs rule – and change of any sort comes at a glacial pace, if at all.

Just this month, federal authorities sued the city to institute reforms at Rikers, saying jail officials had been “deliberately indifferent” to the situation for years.

Indeed, since the early 1980s, six class-action lawsuits have been filed claiming brutality by guards, resulting in court orders to install surveillance cameras and rewrite use-of-force policies.

Jail statistics show use-of-force incidents are up. Inmate stabbings and slashings have more than doubled in the last four years alone, to 88 in fiscal 2014. The system, said jails commissioner Joseph Ponte, “just doesn’t work to keep our staff and inmates safe.”

The crisis of the mentally ill on Rikers came into focus this year after the AP reported the death of Jerome Murdough, a former Marine on psychotropic medication who died of hyperthermia while locked inside a 101-degree cell in February on a trespassing charge. A guard accused of skipping her rounds was charged with falsifying a logbook.

Five months before Murdough’s death, a mentally ill and diabetic inmate died after spending seven straight days in an observation unit. Bradley Ballard, who was locked up alone without his medication after making a lewd gesture at a guard, flooded his cell and tied a rubber band around his genitals.

A series of reports about other inmate deaths followed, spotlighting questionable medical care and suicides that might have been prevented.

At the root of some of these cases is a tension between the two agencies charged with overseeing the inmate population. Health officials call Rikers residents “patients,” while correction officers largely don’t buy that so many inmates really are mentally ill, believing many fake it to avoid being sent to solitary confinement.

“You get inmates that can get one over on Sigmund Freud. They’re that good,” said Jim Garvey, a department chief.

Others point to management turnovers that left less-qualified staff in charge and long-entrenched attitudes among the 9,000 officers who patrol the complex.

“For years the staff there was told the people in Rikers don’t matter and that what they do doesn’t matter,” said Horn. “How do you get that workforce to do its job?”

Norman Seabrook, head of the city’s correction officers’ union, is quick to remind critics that his officers are also “doing time.” Every day a union official sends out an email that notes how many guards were attacked with feces, urine or blood – and how many wound up in the emergency room.

Mayor Bill de Blasio insists that progress is being made in the effort to reform Rikers. Some $32.5 million has been approved for mental health services and more housing, and he’s pledged $130 million more over four years to divert nonviolent people with behavioral disorders to treatment instead of jail.

“It’s a very troubling history,” he said during a visit to the jail, adding that the problems are the result of failed policies and leadership that are now “our moral responsibilities as humans” to resolve.

One day later came the lawsuit by federal prosecutors calling for a court order to bring about “real and lasting change to Rikers Island.”

Ongoing is the investigation into the Oct. 1 death of Victor Woods.

“He was in there … just a week when he died,” said Terri Scroggins, Woods’ longtime girlfriend, who was told by a jail chaplain that Woods apparently suffered a seizure. “He was just a man that had some struggles in life, but he was a good person. He was human.”