OAKLAND, Calif. (AP) — A man charged with fatally stabbing a young woman on a California subway platform was thrown out of court Wednesday after he argued with a prosecutor during opening arguments at his murder trial.

John Lee Cowell ignored the judge's admonishment not to speak and kept disputing whether he or the victim were first to arrive at a Bay Area Rapid Transit station, where surveillance cameras captured the attack in July 2018 that killed 18-year-old Nia Wilson and wounded her 26-year-old sister, Letifah Wilson.

Cowell, 29, a transient with a history of violence and mental illness, was taken out of a packed Alameda County courtroom and missed the rest of the prosecution's presentation to jurors. He has pleaded not guilty to murder and attempted murder with the special circumstance allegation that the stabbings were committed intentionally by lying in wait.

Deputy District Attorney Butch Ford said Cowell followed the women from a platform onto a train for a 30-minute ride to a transfer station and then stabbed them when they exited the train.

Wilson's death was one of several violent attacks on Bay Area Rapid Transit, the train system that connects San Francisco to the nearby cities of Berkeley and Oakland. BART officials have since announced a number of measures intended to improve safety since the attacks that attracted national attention.

The start of the trial had been delayed while authorities sought to determine Cowell's mental competence through a series of psychiatric evaluations. In December, a judge ruled Cowell was fit to stand trial after noting that he was “malingering” and refusing to cooperate with doctors appointed to evaluate him in order to avoid trial.

Cowell was released from a maximum security facility for mentally ill convicts less than three months before the attack. Wilson's sister recovered and was expected to testify for the prosecution.