Attorney General Maura Healey's office plans to formally oppose the bankruptcy petition of Oxycontin manufacturer Purdue Pharma and will seek to keep its own lawsuit against Purdue and its controlling Sackler family alive even as about two dozen states agree to a multi-billion dollar settlement with the company.

After weeks of media reports on the terms of a potential settlement, Purdue filed for Chapter 11 bankruptcy protection in New York late Sunday night and announced that it had agreed to a roughly $10 billion settlement with 24 state attorneys general. As details of the negotiations trickled into the media over the last few weeks, it was clear that Healey opposed any deal that would not force the company's owners to put some of their own money toward the cause.

Under the agreement, Purdue Pharma will reorganize itself through the bankruptcy process as a public beneficiary trust managed by those who filed claims against it for its alleged role in the addiction epidemic. About $7 billion of Purdue Pharma's money, including some in the form of future proceeds from the sale of OxyContin, and a minimum of $3 billion from the personal fortune of the Sackler family, will flow into the new entity. The settlement, according to Purdue, also suggests the "potential for substantial further monetary contributions" from the sales of the Sackler family's ex-U.S. pharmaceutical businesses.

"This settlement framework avoids wasting hundreds of millions of dollars and years on protracted litigation, and instead will provide billions of dollars and critical resources to communities across the country trying to cope with the opioid crisis," Steve Miller, chairman of Purdue's board of directors, said in a statement.

But Healey, who filed the first state lawsuit against individual members of the Sackler family, said Monday that any settlement that does not require the Sacklers to forfeit some of the profits they counted from the sale of opioids is incomplete. She said the Sacklers pulled money from Purdue over many years and stashed it away in offshore accounts, as the New York Times reported Friday, and is now using bankruptcy "as a vehicle to further shield their assets and escape accountability."

Read more: Gov. Baker Stands With AG Healey In Rejecting Purdue Pharma Settlement

"I rejected it for the following reasons: first of all, this proposed deal isn't worth nearly what they say it is. It doesn't require the Sacklers to pay back a dime of the billions of dollars they sucked out of Purdue through the sales of Oxy over the last many years. And also it doesn't provide the kind of accountability and transparency that we need," Healey said Monday. "We need the documents, we need the story told. That's the only way we're going to get justice in this case."

The attorney general said Sackler resources were "not on the table" during recent negotiations, but that the family's personal fortune "needs to be part of the resolution and certainly is something we're going to continue to aggressively pursue."

It was clear Monday that Healey's sights are trained squarely on the Sacklers personally. She declined to say anything directly to the family when asked by a reporter and at one point referred to the Sacklers as "a most unscrupulous and uncaring group of individuals who have caused significant harm."

Healey on Monday also said she is unhappy that the proposed settlement is partially funded through Purdue's continued sale of Oxycontin. She said it makes no sense that a settlement intended to help people in the throes of addiction would be funded by the ongoing sale of potentially addictive painkillers.

"I reject that. That's offensive to me, that we would allow a settlement that allows Purdue and the Sacklers to continue to sell Oxy when everyday people in this country are dying as a result of opioids," she said. "Fundamentally, you look at that and I don't look at that as doing good or being part of the solution, I look at that very differently."

The attorney general said her office will soon make a filing in bankruptcy court in White Plains, N.Y., and will also file with the Massachusetts Superior Court to continue pursuing its suit in that court even as bankruptcy proceedings are ongoing. Healey and her counterpart from New York, Letitia James, are expected to aggressively contest the bankruptcy filing as soon as this week, the Times reported Monday.

"Can't predict how long it will take, it certainly will add some time and complication to things, but at the end of the day we have to operate on principle and we have to do what we think is right," Healey told reporters Monday.

Asked whether she thinks the 24 states that have reportedly agreed to the settlement were wrong to do so, Healey pointed out that there are more states holding out than are going along with the $10 billion settlement.

"Every state I guess has got to make a call for themselves," she said. "The majority of states are still not signed on to the settlement, they're with me on this and many of our larger states included in the group that says no to this proposed deal."

She later added, "I do hope more people will come to see this proposed deal for what it is and, most importantly, for what it is not. It's not accountability, it's not transparency and it's not making the perpetrators pay."

Healey first sued the Sackler family and Purdue Pharma in June 2018, alleging that they "engaged in a deadly, deceptive scheme to sell opioids in Massachusetts" and profited from the drug epidemic they helped create.

Healey's complaint alleges that Purdue "created the epidemic and profited from it through a web of illegal deceit" by misleading doctors and patients to get more people using their drugs, at "higher and more dangerous doses" and for longer periods of time, as well as by deploying falsehoods to keep patients away from "safer alternatives."

A total of 671 Massachusetts residents who filled prescriptions for Purdue opioids since 2009 later died of an opioid overdose, according to the suit. According to Healey's office, Purdue sent sales representatives to Massachusetts doctors offices, clinics and hospitals more than 150,000 times since 2008.

Purdue reported Sunday that it has received FDA fast-track designation for nalmefene hydrochloride, which the company described as a "much-needed treatment that has the potential to reverse overdoses from powerful synthetic opioids such as fentanyl." The settlement, which is subject to court approval, could result in the new trust contributing "tens of millions of doses of opioid overdose reversal and addiction treatment medications at no or low cost," according to Purdue.

A hearing on initial motions in the bankruptcy case is scheduled for 10 a.m. Tuesday before Judge Robert Drain in White Plains, N.Y.