A third woman who also was involved with him told her story to the other two women, but said she was too frightened to come forward.
A fourth woman said Schneiderman slapped her when she rebuffed him, but also asked to remain unidentified.
The New Yorker said it vetted the third woman's allegations, and saw a photo of what the fourth woman said was her injury.
The two women who spoke on the record, Michelle Manning Barish and Tanya Selvaratnam, both said the physical abuse escalated over time, and that Schneiderman also was a heavy drinker.
AP is identifying the women because they agreed to tell their stories publicly.
Asked for comment, Schneiderman, a Democrat, initially issued a statement to the New Yorker saying, "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 non-consensual sex, which is I line I would not cross."
His representatives sent the same statement to AP when asked about the accusations.
They also sent a statement from his ex-wife, Jennifer Cunningham, who said, "I've known Eric for nearly 35 years as a husband, father and friend. 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."
But four hours after the story broke, Schneiderman resigned.
He said the allegations will "effectively prevent him from leading the office's work" and therefore will resign on the close of business tomorrow.
Schneiderman says it's been a great honour and privilege to serve as attorney-general. He says he strongly contests the allegations, which he calls unrelated to his professional conduct or operations of the office.
Schneiderman has been a vocal supporter of the #MeToo movement.
He filed a lawsuit in February against movie producer Harvey Weinstein and the Weinstein Co. following an investigation into allegations of sexual misconduct, saying the company broke New York law by failing to protect employees from "pervasive sexual harassment, intimidation and discrimination".
He launched a civil rights probe into the New York City-based company in October after the New York Times and the New Yorker exposed allegations of sexual assault and harassment spanning decades. The company later fired Weinstein.
The women accusing him said seeing him speak out on sexual misconduct issues was part of the impetus in them coming forward.
"This is a man who has staked his entire career, his personal narrative, on being a champion for women publicly," Selvaratnam said. "But he abuses them privately. He needs to be called out."
-AP
