Two cousins charged in the kidnapping and torture of a Jewelers Row shop employee were ordered held without bail Monday.

But lawyers for Basil Buie, 26, and Salahudin Shaheed, 35, characterized the case against their clients as "thin" and based primarily on testimony from Khayree Gay, 31, a third codefendant with a "motive to lie."

"At this point, we have one source connecting my client to this crime, and it's a complicated source: Mr. Gay," Coley O. Reynolds, lawyer for Shaheed, said during a hearing before U.S. Magistrate Judge Elizabeth T. Hey.

Federal prosecutors have not identified Gay, who was arrested in South Carolina on April 10, as the informant who provided the most complete information linking Buie and Shaheed to the April 4 abduction. But his involvement as a key witness is clear from court documents and information investigators have given out about the case.

At Monday's court hearing, Sarah O'Reilly, the case agent from the Bureau of Alcohol, Tobacco, Firearms and Explosives, outlined the story Gay told authorities last week.

According to court filings, he painted Shaheed as the mastermind behind the attack, and said he had accompanied him as he and Buie surveilled their victim for days before grabbing her as she left the National Watch & Diamond Exchange, 101 S. Eighth St.

Prosecutors say the trio put a bag over her head, bound her with zip ties, beat her, and used a Taser on her at least seven times as they demanded she give up the code to the store's safe.

Buie, a heavyset man, allegedly sat on top of the woman as Shaheed drove her and her captors around town for more than two hours, and used her debit card at ATMs at a Wawa store and a Chinese restaurant.

"It was this defendant that sat on the victim while she was spitting up bile because her beating was so severe," said Assistant U.S. Attorney Jeanine M. Linehan, referring to Buie. "Her hands turned blue from her restraints."

Another cooperating witness told agents last month that he picked up Gay and two other men on the day of the attack. That source later identified Shaheed in a photo lineup as one of the men with Gay that day.

When presented with a separate lineup, the witness indicated Buie, saying he believed him to be the other man in the car, but that he could not be certain, ATF's O'Reilly said.

Though Reynolds and Arnold C. Joseph, lawyer for Buie, attacked Gay's version of events Monday, Linehan told the judge that other evidence corroborated Buie and Shaheed's connection to the attacks.

And Hey agreed, clearing the case for trial and ordering the cousins held in federal detention and kept separate from Gay, who also remains in custody.

All three men are being held on federal charges of attempted robbery. Gay has also been charged with kidnapping, a charge Buie and Shaheed are also likely to face once their case goes before a grand jury.

Buie has no prior criminal record, his lawyer said Monday. Linehan argued that several text message exchanges found on his cellphone suggest he might have been involved in selling crack cocaine.

Shaheed has a lengthy rap sheet including several drug convictions.

jroebuck@phillynews.com

215-854-2608 @jeremyrroebuck