KRON4’s Amy Larson is in court daily to bring you updates on the trial of Nia Wilson‘s killer. Find all her stories here.

OAKLAND, Calif. (KRON) — John Lee Cowell was back on the stand to testify in his own murder trial Thursday, but only lasted about 25 minutes before being thrown out of court.

KRON4 Digital Reporter Amy Larson says Cowell, who’s on trial for the murder of Nia Wilson, went off on a profanity-laced rant before being escorted out of the courtroom.

When Cowell took the stand Thursday, he almost immediately became combative with Alameda County prosecutor Butch Ford.

Cowell really got agitated when Ford tried to play surveillance video showing Cowell attacking Wilson.

Cowell hurled several expletives at Ford and, at one point, told Ford to “back the f**k down.”

The judge told Cowell that if he couldn’t refrain from using vulgar language, he would be taken out of the courtroom.

Cowell continued on his profanity-laced rant, so deputies escorted him out of the courtroom.

Prosecutors told KRON4 that Cowell’s testimony is over and he will not take the stand again.

Cowell first took the stand on Tuesday. He testified about his state of mind when he stabbed Wilson and his her sister on a BART platform in Oakland.

He said that he believed 18-year-old Wilson and her two sisters were “aliens” and “gang members” who kidnapped his grandmother and were going to hurt her.

Cowell, 29, of Concord, said he was trying to save his grandmother by stabbing “the black females.”

Cowell suffers from schizophrenia, and he has pleaded not guilty by reason of insanity. 

This is not the first time he has been forced to leave the courtroom during this trial.

Last Wednesday, he was removed from the courtroom for making an outburst just two minutes into the prosecutor’s opening statement.

As the trial continued, Cowell remained in a separate room in the Oakland courthouse. Deputies tasked with guarding him tried to coax Cowell to walk downstairs to the courtroom, but he refused to.

This story is still developing. Check back for updates

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