Sniper John Allen Muhammad wriggled out of a waist chain during a break in a pretrial hearing in Fairfax County yesterday, then calmly walked back into the courtroom with the chain still attached to his handcuffs.

The hearing resumed for less than a minute before a sheriff's deputy noticed that the chain was not around Muhammad's waist. Fairfax Circuit Court Judge Jonathan C. Thacher abruptly adjourned the hearing and left the courtroom. Muhammad was hustled into an adjacent holding cell, and the chain was replaced.

The chain "could have been used as a weapon, but it wasn't," Lt. Tony Shobe of the Fairfax sheriff's office said after the hearing. The hearing then proceeded without incident, though the waist chain was gone after lunch, and Muhammad stood behind the lawyers at a bench conference with his arms free. The death row prisoner was still in handcuffs and leg shackles and closely guarded.

The first hearing on pretrial motions in Muhammad's second capital murder trial held few other surprises. Thacher declined a defense request to disqualify Fairfax prosecutors from the case, and the defense withdrew its motion to move the trial out of Fairfax, though it may be refiled.

The day ended with a 10-minute bench conference in which Muhammad's attorneys apparently raised the issue of postponing Muhammad's trial, set for Oct. 4.

After the hearing, court officials said Thacher had ruled that the contents of that conference, and all bench conferences, would be sealed from the public for the entire trial. No reason was given for sealing the on-the-record comments, which are typically available.

Muhammad, 43, is being prosecuted in Fairfax in the October 2002 slaying of Linda Franklin outside the Seven Corners Home Depot. He was convicted last fall by Prince William County authorities for the killing of Dean H. Meyers, part of a string of 10 fatal shootings in a three-week period. A jury sentenced him to death.

Fairfax sheriff's officials did not classify yesterday's maneuver by Muhammad as an escape attempt, but it was the second instance of odd behavior. Muhammad entered the courtroom barefoot. Shobe said Muhammad refused to wear shoes, and deputies decided not to force the issue.

Muhammad was handcuffed, and a waist chain was threaded through the cuffs to keep his hands close to his body. Shortly before noon, Thacher took a 15-minute recess. Shobe said that while Muhammad was seated in his holding cell, he placed his hands beneath his legs and shook his way out of the chain.

The chain then hung from Muhammad's wrists, though it was not obvious when he walked back into court. Deputies watched him during the hearing and noticed that the chain was not around his waist.

After the chain was replaced and Muhammad returned, Thacher admonished him. "This is the one and only security violation I will tolerate," Thacher said, warning that he could impose electric shock devices to keep Muhammad secure.

After lunch, deputies decided not to put the chain back on Muhammad, Shobe said. Muhammad was still cuffed and shackled.

Defense attorney Peter D. Greenspun argued that Commonwealth's Attorney Robert F. Horan Jr. and all Fairfax prosecutors should be tossed off the case because Horan previously argued that Muhammad's co-conspirator, Lee Boyd Malvo, was the person who shot and killed Franklin. The defense believes Muhammad is not eligible for the death penalty if he is not shown to have fired the fatal bullet, and they said they would call Horan as a witness to testify about his belief that Malvo was the triggerman, thereby disqualifying him as prosecutor.

Horan said he would continue to argue that Malvo was the gunman but that Muhammad was equally culpable for planning, driving and spotting for Malvo during the shootings. "Both Muhammad and Malvo were peas in a pod," Horan said. "They were two evil human beings that embarked on a series of murders to get money."

Thacher declined to recuse the prosecutors but said he would rule later on whether Muhammad could face the death penalty.

Fairfax prosecutors won't be barred from Muhammad's case.