CENTENNIAL, Colo. (AP) -- Months before James Holmes opened fire in a Colorado movie theater, his ex-girlfriend said she asked him to see a therapist after he mentioned having thoughts about killing people, but his thoughts "seemed very philosophical" and not a concrete threat.

Gargi Datta, a former girlfriend of Colorado theater shooter James Holmes, is questioned by District Attorney George Brauchler, during a trail for Holmes, in Centennial, Colo.

Gargi Datta also testified Thursday that during their relationship, Holmes showed no interest in guns, including when they visited an outdoor store that sold weapons.

Datta and Holmes were graduate students at the University of Colorado-Denver when they began dating during their first semester in the fall of 2011.

By February 2012, she said, she did not want anything more than a casual relationship, and the two remained "friends with benefits" until Holmes told her in early April he could not continue. After that, Datta said, she did not communicate with Holmes and only saw him in the classroom.

District Attorney George Brauchler has said their breakup was a catalyst to the July 20, 2012, shooting at a suburban Denver movie theater. He said Datta was Holmes' first romantic relationship.

Holmes has pleaded not guilty by reason of insanity in the attack that killed 12 people and injured 70. Prosecutors contend Holmes was sane, and they are seeking the death penalty.

Datta told defense attorney Tamara Brady on Thursday that she never saw Holmes with the orange hair and dilated eyes that marked his first court appearances after the shooting. Brady displayed those photos of Holmes in court as she asked the question.

In March 2012, Datta said, she received an electronic message from Holmes that prompted her and a friend to ask Holmes to see a therapist. Holmes said he already was. Datta did not elaborate, and the contents of the message were not read aloud in court.

Their first date was a horror film festival and they grew closer after that, sharing nights together at home watching movies or playing board games with friends.

They started spending time together after she invited him to a study session. Holmes emailed his phone number to her and said that if she texted him, "I will tell you an amazingly, best-ever world's greatest knock-knock joke."

Datta said they were spending one or two nights a week together in the months before the shooting. After they broke up, Holmes never revealed to her that he was amassing an arsenal of weapons and body armor in meticulous preparation for the attack, prosecutors said.

In court, Datta never looked directly at Holmes and repeatedly referred to him as "the defendant" rather than his name. Holmes swayed in his chair as she spoke but had no other visible reaction.

In a video played earlier in the trial, Holmes said he fell in love with Datta. He had written about her in emails to his parents, saying he had cooked dinner for her on Valentine's Day. The two played board games together with friends, watched movies at home, shared dinners and were in the same stressful classes, Datta said.

But Datta said she wanted to end the relationship in January 2012 when she returned from winter break.

"I had already told him in the start that it was a casual relationship," she testified. "I didn't feel I was getting closer to him. I think he liked me more than I liked him."

Datta concluded her testimony but was told by the judge she could be summoned back.

Also Thursday, the judge said that a juror would remain on the panel after her brother-in-law was shot three times during an armed robbery Wednesday in Denver. The juror told the judge her brother-in-law is expected to recover and that the incident will not affect her service on the jury.

Earlier this week, three jurors were dismissed amid concerns they had seen news reports about the case.

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