John Allen Muhammad tangled with Lee Boyd Malvo in an aggressive cross-examination of his former protege yesterday, then erupted in anger at prosecutors who tried to limit Muhammad's questioning in his sniper murder trial.

A day after Malvo offered a startling insider's account of being the junior member of the sniper team that terrorized the Washington area, Muhammad sought to undercut Malvo's credibility by focusing on his insanity plea in his 2003 Virginia murder trial.

"How many experts was it that said you was insane?" Muhammad, 45, demanded of Malvo, 21, challenging claims that Muhammad had brainwashed him.

Malvo replied that two experts testified to the finding. He had pleaded not guilty by reason of insanity because of indoctrination, a claim jurors rejected in convicting Malvo of murder.

Muhammad grew exasperated as Montgomery County Circuit Judge James L . Ryan sustained Deputy State's Attorney Katherine Winfree's frequent objections to Muhammad's queries.

"Your honor, she needs to make her objection and sit down," Muhammad shouted after Winfree objected to questions about what Malvo now says was a false confession to all the sniper slayings, given to Virginia investigators shortly after the pair's arrest Oct. 24, 2002.

Malvo said again yesterday that he lied to detectives because of a pact with Muhammad to protect the older man from the death penalty in the event the pair were arrested.

During several hours of cross-examination, Malvo responded evenly and with carefully chosen words to Muhammad's questions.

"At any time did John Allen Muhammad go into that area?" Muhammad asked, referring to the woods near the Bowie middle school where 13-year-old Iran Brown was shot and wounded Oct. 7, 2002.

"No. You sent me in," Malvo coolly asserted.

After Malvo stepped down, prosecutors rested their case and Muhammad began his defense. However, court records show that only three of about two dozen subpoenas have been served.

Muhammad, who has been sentenced to death in Virginia for one sniper murder, is on trial in Montgomery County for six sniper killings in fall 2002.

He has represented himself since firing his public defenders when they contended he was too mentally ill to stand trial. A psychiatrist has said the Gulf War veteran - who previously claimed that former Attorney General John D. Ashcroft was part of a conspiracy to frame him in the sniper shootings - is delusional.

In jarring testimony Tuesday, Malvo said that Muhammad had initially planned for the pair to carry out six shootings a day for one month. Then Muhammad decided to shift to "Phase 2" of the plan, but the two were arrested the day they were to embark on it.

With Baltimore as the hub, Muhammad wanted to shoot a police officer, then set off explosives against other officers and mourners at the cemetery as the funeral was taking place, and plant homemade bombs on buses to kill elementary school children, Malvo testified. With the $10 million they would have extorted from the government to end the killing, Muhammad wanted to set up a 140-child community in Canada to train young terrorists whose actions would ruin the U.S. economy, Malvo said.

Malvo testified that Muhammad turned him "into a monster," taking him from the Caribbean to the United States, filling his head with hatred and violence and training him to shoot.

According to Malvo, Muhammad told him in early 2002 that they would go to Maryland to retrieve his three biological children, whom he had lost in a custody dispute. In July 2002, Muhammad unveiled a murderous mission to accompany that plan.

Malvo told jurors Tuesday that he was so upset over Muhammad's scheme that he spent about two hours in a bathroom playing Russian roulette with a handgun but could not fire the bullet to kill himself. Instead, he broke down and cried, he said.

As Muhammad got Malvo to acknowledge yesterday that he treated him like one of his children, Malvo's voice grew quiet in the witness box.