BUFFALO, N.Y. (AP) — Two homeless men accused of killing a concert violinist during a robbery in her rural home were ordered held without bail Thursday after a prosecutor detailed how the 61-year-old musician was shot twice and stabbed after opening her door to let them use her phone.

“They obviously preyed upon her willingness to assist them,” Assistant U.S. Attorney Timothy Lynch said in arguing against the release of Jonathan Conklin, 43, and Charles Sanford, 30, pending further proceedings. Conklin and Sanford have pleaded not guilty to federal charges of carjacking, using a gun during a violent crime and bringing a stolen vehicle across state lines. A Chautauqua County grand jury will consider state murder charges, prosecutors have said.

Two friends found Mary Whitaker’s body Aug. 20 in the attached garage of the Westfield home where she lived during the summer while performing at the Chautauqua Institution, a lakeside arts and intellectual community in western New York.

Sanford and Conklin were arrested two days later in nearby Erie, Pennsylvania, where the victim’s stolen vehicle was recovered and where her credit card had been used hours after her death to purchase a flat-screen television at a Wal-Mart, authorities said. Both men have confessed, Lynch said.

The prosecutor’s account and court documents detail how the suspects, who had met months earlier at an Erie homeless shelter, planned and carried out the robbery. Conklin “wanted to live like a rock star” and needed money to buy drugs, Sanford told investigators, according to an FBI agent’s affidavit filed in support of the criminal charges.

Neither Conklin nor Sanford, who both have criminal records, spoke during Thursday’s detention hearing. Sanford’s assigned attorney, Mark Mahoney, said afterward that he had yet to view the police interviews of the suspects recorded after their separate arrests.

“I do understand (Conklin) may be trying to switch the blame onto Mr. Sanford,” Mahoney said. “That’s not surprising. It happens a lot.”

Public defender Kimberly Schechter, who is representing Conklin, did not immediately return a phone message.

In court Thursday, Lynch described how, with Conklin hiding out of sight, Sanford knocked on the door of Whitaker’s ranch-style home about 6:45 a.m. Aug. 20 and asked to use her phone, telling her his vehicle had run out of gas. Whitaker gave her phone to Sanford, who began dialing.

“With that ruse, it was Mr. Conklin who came out and shot Miss Whitaker in the torso,” Lynch said.

She was shot again in the leg before Sanford dragged her into the garage and joined Conklin in searching Whitaker’s home for valuables, the prosecutor said. Afterward, “while she was gurgling on her own blood, Mr. Sanford then stabbed Miss Whitaker in the neck,” Lynch said.

The Chautauqua Symphony Orchestra had performed its last concert of the season the evening before. During the rest of the year, Whitaker lived in New York City and performed with the Westchester Philharmonic Orchestra and on Broadway shows.

A tribute on the downstate orchestra’s website called her a “true and caring friend and an exquisite artist.”

Sanford was convicted in 2012 of statutory sexual assault. Conklin has four felony convictions, including for burglary, and was wanted for grand larceny at the time of his arrest.

A preliminary hearing was scheduled for Sept. 9.