The Denver Post via AP, Pool, Andy Cross
In this June 4, 2013 file photo Aurora theater shooting suspect James Holmes appears in court in Centennial, Colo. A former girlfriend of the Colorado theater shooter described him as bright but shy in the classroom Wednesday and testified in his death penalty trial that they went to a horror film festival on their first date.

CENTENNIAL, Colo. — A former girlfriend of Colorado theater shooter James Holmes described him as bright but shy in the classroom Wednesday and testified in his death penalty trial that they went to a horror film festival on their first date.

In brief questioning before court adjourned for the day, Gargi Datta said she met Holmes in 2011 at the graduate school they attended outside Denver. Holmes was a promising neuroscience postgraduate at the time.

"He was pretty shy and closed off at school. He wouldn't go up and interact with people," Datta said.

She also said Holmes wanted more than the casual relationship she preferred during their time together.

Datta said she went to Holmes' apartment in February 2012 — five months before the theater shooting — to break up with him. "I told him I saw no future for us," she said. "I think he liked me more than I liked him."

Datta will take the stand again Thursday.

Prosecutors have said Holmes described his "evil plan" to his girlfriend as he was buying an arsenal of weapons and went to a remote shooting range in the months before the attack.

Holmes has pleaded not guilty by reason of insanity in the July 2012 shooting at a suburban Denver movie theater that killed 12 people and injured 70. Prosecutors contend Holmes was sane and are seeking the death penalty.

Datta's testimony came a day after the judge dismissed three jurors who had been exposed to news reports about the case.

The discovery that a juror had heard news accounts of the trial and shared details with the other two stalled Tuesday's testimony but did not derail the case. Judge Carlos A. Samour Jr. had seated 12 alternate jurors, an unusually large number, aware of the possibility of media exposure.

"The judge knew that given the attention and the amount of information that's out there, there's a good chance that some jurors are going to disobey him and do what's natural," said Alan Tuerkheimer, principal of Trial Methods, a Chicago-based jury consulting firm.

The dismissals came in the trial's seventh week. The first juror said her husband told her on speakerphone that the district attorney had sent a tweet during testimony, which had been in the news.

The other two jurors, who sometimes socialized with the first juror on breaks, were dismissed because they likely overheard her. The judge questioned the jurors individually about what they had heard and wasn't convinced they were being forthcoming.

He decided against releasing a fourth juror who said she had heard the word "mistrial" but didn't know what it was about.

Samour also refused a defense request to dismiss a fifth juror who had informed him about the situation, saying she had been honest and wasn't compromised.

"Thank you for doing the right thing," he told her when she came forward, visibly distraught.

A total of 21 jurors and alternates remain, with the trial more than halfway done. The problem could have had greater consequences had it been discovered closer to deliberations, Tuerkheimer said.

A similar situation with fewer alternates might have caused a mistrial, he said.

Last week, the judge scolded District Attorney George Brauchler for tweeting from the courtroom about a videotaped interview of Holmes shown to jurors. He said it was an accident and apologized.

Associated Press writer Donna Bryson contributed to this report from Denver.