The law school graduate arrested in the beating death of his girlfriend in Astoria last month is suffering from "extreme emotional disturbance," his attorney said after a court hearing Monday.

Jason Bohn, 33, was arraigned and held without bail after pleading not guilty to charges including murder, strangulation and harassment.

He was initially arrested on lesser charges after Danielle Thomas, 27, was found dead June 26 inside the Astoria, Queens apartment she had rented with him. But Queens District Attorney Richard A. Brown upgraded the charges because he said Bohn intended to torture Thomas inside their home.

Bohn's attorney, Todd Greenberg, said he did not believe there are facts to back up a charge of premeditated murder. He said his client had been suffering from emotional disturbances, but wouldn't say whether his client had a history of mental illness.

"I think in the end it's not going to be a case of 'who done it' but rather 'why it was done,'" Greenberg said. "We expect extreme emotional disturbance to be part of this case."

Thomas, a financial analyst for Weight Watchers, told police on June 7 that Bohn had beaten her in May, leaving her with two black eyes and on crutches. She said Bohn also was sending her threatening emails and text messages.

While she was at the police station, Bohn called her cellphone, which she placed on speakerphone, prosecutors said during a previous hearing. Police heard him say he would bash in her skull after hunting her down like a dog, prosecutors said.

Bohn, a graduate of the University of Florida's law school, was arrested that day, arraigned and released. Thomas received an order of protection against him.

She was found dead on June 26. Her body was lying face up in the bathtub surrounded with bags of ice, and there were was bruising on her face, shoulders and neck, and lacerations on her face, mouth and chest. The cause of death was blunt force trauma to the neck and torso. She was believed to have been killed the previous weekend.

Prosecutors said Bohn called police the day Thomas' body was found and said he was out of town but wanted to report a "domestic incident," saying he'd gone to a party with Thomas, gotten drunk and passed out. They said he told police that when she tried to wake him, he got angry and threw her against the wall, and she was unconscious.

"I want someone to check on her to make sure she's all right," he said, according to prosecutors.

Thomas, 27, a native of Danville, Ky., attended both the University of Florida and University of Central Florida, where she was a member of the Eta Sigma Delta Honor Society, according to her obituary.

When her body was found, police also discovered two handwritten notes.

According to prosecutors, one read: "It was an accident, it was an accident, it was an accident," and went on to again describe how he had been drinking and they fought.

The other read: "Dani, I will love you forever."

The note was signed "J."

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