WASHINGTON, Feb. 6 -- Zacarias Moussaoui, the only person to be put on trial in the United States for involvement in the Sept. 11 terrorist attacks, was ejected from a federal courtroom at the start of jury selection today after an outburst in which he shouted, "I am Al Qaeda."

When he was first escorted into the federal courtroom in Alexandria, Va., Mr. Moussaoui slowly panned the spectators' section to look at the pool of people from which the jury will be selected. Because he has already pleaded guilty to six felony counts of conspiracy in connection with the attacks, the only question for the jury is whether he should be executed by lethal injection or remain in jail for the remainder of his life.