The Manhattan district attorney has launched an investigation into the abuse allegations against Eric Schneiderman, the New York attorney general who abruptly announced his resignation Monday after the accusations were made public in a New Yorker story.

The investigation comes amid a remarkably swift fall for Schneiderman (D), a high-profile figure who had publicly been an advocate for women while serving as his state’s top law enforcement official. Schneiderman has denied the allegations of abuse that were laid out in painful detail in the magazine article, which included multiple accounts of women saying he slapped and choked them.

About three hours after the New Yorker article was published, Schneiderman said he would step down, with his resignation taking effect on Tuesday. Even as he leaves office, Schneiderman will remain the focus of another New York law enforcement official. A spokesman for Cyrus R. Vance Jr., the Manhattan district attorney, said in a statement that his office “has opened an investigation into the recently reported allegations concerning Mr. Schneiderman.”

The investigation from Vance’s office highlights the sea change for Schneiderman. Just two months earlier, Schneiderman had been tasked by Gov. Andrew M. Cuomo (D) with investigating how Vance’s office handled a sexual assault allegation against the movie producer Harvey Weinstein. At the time, Schneiderman said his office was “deeply familiar with Harvey Weinstein’s years of egregious sexual abuse,” having just filed a civil rights lawsuit against the producer and his company.

James P. O’Neill, the New York City police commissioner, said the department’s chief of detectives had spoken Tuesday morning with Vance about the “very serious allegations” against Schneiderman. O’Neill said he would not speculate about what charges Schneiderman could face.

Authorities plan to contact the people identified in the article to conduct “a full investigation” into the accusations, O’Neill said at a news conference that had been intended to discuss crime statistics. As of Tuesday afternoon, police have not received any complaints regarding Schneiderman, O’Neill said.

O’Neill said he was comfortable about working with Vance’s office even though Schneiderman had previously been tasked with investigating the Manhattan district attorney’s office.

Schneiderman said his resignation would be effective “at the close of business” on Tuesday. The New York attorney general’s office said Barbara D. Underwood, the New York solicitor general, would become the acting attorney general.

Underwood, who was appointed solicitor general in 2007, has held roles in the U.S. attorney’s office for the Eastern District of New York as well as the district attorneys’ offices in Manhattan, Queens and Brooklyn, according to the attorney general’s office. The office also said she has also argued 20 cases before the U.S. Supreme Court.

“I am honored to serve the people of New York as acting Attorney General,” Underwood said in a statement Tuesday. “The work of this office is critically important. Our office has never been stronger, and this extraordinarily talented, dedicated, and tireless team of public servants will ensure that our work continues without interruption.”

In the New Yorker story published Monday, two women — Michelle Manning Barish and Tanya Selvaratnam — said they had been in romantic relationships with Schneiderman when he choked and slapped them, causing them to seek medical treatment. The article also said a third woman made accusations of physical violence, while a fourth woman said that when she rejected one of Schneiderman’s advances, he “slapped her across the face with such force that it left a mark that lingered the next day.”

Schneiderman said in a statement: “In the privacy of intimate relationships, I have engaged in role-playing and other consensual sexual activity. I have not assaulted anyone. I have never engaged in nonconsensual sex, which is a line I would not cross.”

All four women said their physical abuse was not consensual. Selvaratnam described escalating physical attacks, telling the magazine that the slaps grew in strength.

“It wasn’t consensual,” she said in the story. “This wasn’t sexual playacting. This was abusive, demeaning, threatening behavior.”

The descriptions of abuse in the New Yorker story also extended to emotional and psychological torment. Selvaratnam said Schneiderman warned her he could have her followed and her phones tapped, and both women named in the article said he threatened to kill them if they ended their relationships with him.

After the New Yorker article’s publication, Manning Barish tweeted a link to it and wrote: “After the most difficult month of my life-I spoke up. For my daughter and for all women. I could not remain silent and encourage other women to be brave for me. I could not.”

Jennifer Cunningham, Schneiderman’s ex-wife and a political strategist, released a statement Monday saying she was surprised by the accusations.

“I’ve known Eric for nearly thirty-five years as a husband, father, and friend,” she said. “These allegations are completely inconsistent with the man I know, who has always been someone of the highest character, outstanding values, and a loving father. I find it impossible to believe these allegations are true.”

New York Mayor Bill de Blasio (D) said Tuesday that he was “horrified” to read the allegations against Schneiderman.

“The attorney general of our state, accused of doing things that no one should ever do, let alone someone involved in law enforcement,” de Blasio said at the news conference with O’Neill. He described reading the article and finding that “page after page, it got worse and worse and worse.”

“No one can do this to another human being,” De Blasio said. “You can’t abuse people, you can’t harass them, you can’t use your power against them, you can’t threaten them. You just can’t do that.”

De Blasio said he was happy Schneiderman resigned quickly and added that he hopes any other people who say they were victims of Schneiderman come forward and contact police.

“Rest assured, you will be believed and that the information will be important to protecting others,” he said.

Schneiderman, who was first elected in 2010 and was up for a third term this year, was perhaps best-known nationally for his persistent legal challenges to President Trump. His biography posted on the attorney general’s site lists a series of these actions, including challenging Trump’s entry ban and advocating for sanctuary cities.

Before Trump took office, Schneiderman filed a lawsuit against Trump University, the now-defunct real estate seminar program, and opened an investigation into the president’s charitable foundation. More recently, Schneiderman has pushed for the state to alter its laws so that his office could prosecute those people connected to Trump who may get pardoned by the president. Supporters of Trump appeared to revel in the allegations against Schneiderman and his resignation.

The New Yorker article  was written by Jane Mayer, a celebrated reporter for the magazine, and Ronan Farrow, who recently shared in a Pulitzer Prize for his reporting on accusations against Weinstein. When Farrow and journalists for the New York Times won that award, Schneiderman’s Twitter account tweeted that it was “a well-deserved honor” and praised their reporting as well as “the brave women and men who spoke up about the sexual harassment they endured at the hands of powerful men.”

New York State Attorney General Eric Schneiderman in his office last year. (Frank Franklin II/AP)

On Monday night, the New Yorker’s article prompted a firestorm of criticism. Prominent Democrats like Cuomo and Sen. Kirsten Gillibrand said he should step down, as did the New York GOP, which called the accusations “dark and disturbing.” Not long after, Schneiderman said he would leave office.

“In the last several hours, serious allegations, which I strongly contest, have been made against me,” Schneiderman said Monday night in a statement. “While these allegations are unrelated to my professional conduct or the operations of the office, they will effectively prevent me from leading the office’s work at this critical time.”

This story has been updated since it was first published.

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