As the hunt for the hatchet-wielding murderer of a New York psychologist intensified Friday, police fought for access to patients' medical records and provided more clues into the killer's actions moments before the attack.

Detectives have studied Kathryn Faughey's e-mails and phone calls, but aren't able to look through her work files because of federal privacy laws. Investigators have theorized that the vicious murderer could be one of Faughey's patients.

New York City Police Commissioner Ray Kelly said the department was trying to petition the court, through the district attorney's office, to access Faughey's records. He wasn't sure how long the effort would take.

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Also Friday, police shed more light on events leading up to the stabbing of a psychologist in her office, saying the killer was in a waiting room with another patient for nearly a half hour before the bloody attack.

Kelly said the slasher arrived at 8 p.m., telling the doorman he had an appointment with a psychiatrist in the building, Dr. Kent Shinbach, then sat in the waiting room with another of Shinbach's patients until she went into his office around 8:30 p.m.

Sometime after that, the killer entered Faughey's office and attacked her. Shinbach came to her aid, but was assaulted and robbed.

The killer then tried to force Shinbach's patient, who had been in Shinbach's office during the attack, into a bathroom; she kicked at him and he fled through a basement door, Kelly said.

It wasn't clear if the suspect was injured; blood was spattered on the walls and pooled on the floor of Faughey's office. Blood also was found on the basement door, police said.

The federal privacy law in question requiring a court's involvement to obtain medical records is known as the Health Insurance Portability and Accountability Act of 1996 and mandates that doctors, hospitals and insurance companies protect patients' confidentiality.

Generally, that means a subpoena is needed to access medical records in situations like a murder case. Patients are allowed to sue if they choose to fight the subpoena.

Adding to the difficulty in unraveling the mystery is that Faughey didn't sound worried about her safety in the hours before she was butchered in her office, according to a friend who exchanged e-mail messages with her that evening.

On her mind, though, was another member of their circle of guitar enthusiasts, a man she had offered help with personal problems. Faughey mentioned him in her last message, sent only about half an hour before the killing, said her friend Don Hurley.

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Detectives interviewed the man, William Kunsman, Thursday in Pennsylvania. He was not considered a suspect, but the development showed how determined investigators were to track down any clues into the mystery slasher.

The killer slashed Faughey 15 times with a meat cleaver and a 9-inch knife in her Manhattan office Tuesday evening.

Investigators continued probing for evidence Friday, removing nine boxes from Faughey's office.

Kunsman met Faughey, 56, at a guitar camp several years ago, and they were friends, according to a law enforcement official who spoke on condition of anonymity because the investigation is ongoing.

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Kunsman was found through Faughey's recent e-mail records, which contained messages about his personal problems, the law enforcement official said. Pennsylvania state troopers picked him up at his home without incident at around 4:30 a.m., and he was let go eight and a half hours later, after he asked for a lawyer, the official said.

"The reasons they had for questioning me were valid," said Kunsman, of Coplay, Pa., adding that he was "extremely saddened" to hear of Faughey's death. "I've been in more contact with Kathryn lately. I've been speaking to her a lot lately on the phone and by e-mail. I guess that's what led them here."

Kunsman, who is married with six children, last spoke to Faughey on Tuesday afternoon but declined to say what their conversation was about. "That's personal. She was just being a friend," he said.

Hurley, who knew Faughey through an online club for people interested in C.F. Martin & Co. guitars, said he and Faughey traded e-mail messages on the evening of her death about a variety of topics, including Kunsman. Hurley, a recently retired Sunday Times of London reporter, said Faughey had reached out to Kunsman after he "lost his way a little bit" and offered some help.

In her last message, sent about 30 minutes before the killing, Faughey mentioned Kunsman but gave no indication that she was concerned about her safety, or that she was expecting any visitors that evening.

Hurley said he found it hard to believe Kunsman had anything to do with the attack, a view echoed by Faughey's husband, Walter Adam. He told reporters Kunsman was a friend of the couple.

Kunsman did not appear to be injured; police initially indicated that the killer might have suffered wounds from the struggle.

Kunsman said the detectives never referred to him as a suspect during the questioning. "The reason it took so long is so they could ... verify what I was telling them was the truth," Kunsman said.

"I had no idea what was going on because I hadn't even heard the news about Kathryn. It didn't become clear to me until during the questioning what had happened," he said.

The suspect left behind several clues, dropping two bags near the basement door through which he escaped. The bags were filled with adult diapers, women's clothing, rope, duct tape and eight knives apparently not used in the attack, police said.

The diapers were of a type not widely distributed but available near Bethlehem, Pa., officials said.

Police recovered three other knives at the scene of the killing, including the 9-inch knife and the meat cleaver.

The suspect told the East 79th Street building's doorman he had an appointment with Shinbach, a 70-year-old geriatric psychiatrist. At some point, the suspect went into Faughey's office and started to attack her, police said. When Shinbach responded to her screams, the attacker stabbed him, pinned him to the wall and stole $90 from his pocket.

Shinbach was taken to New York-Presbyterian Hospital/Weill Cornell Medical Center with slash wounds on his head, face and hands. The hospital declined to release any information about Shinbach on Thursday; police believed he remained in serious but stable condition.

Faughey, a licensed psychologist, described herself as a specialist in cognitive behavioral therapy. It focuses on changing thoughts that cause feelings or behaviors.

She was also an avid guitar player. In the past few years, she had attended several of the group's get-togethers in Pennsylvania and elsewhere and had become fast friends with some of her fellow Martin enthusiasts.

The Associated Press contributed to this report.