DALLAS (CBSDFW.COM) – Local activists are calling for the firing of a Dallas police officer after prosecutors revealed text messages between him and Amber Guyger on the night Botham Jean was killed, along with the deletion of those messages.

Senior Cpl. Martin Rivera, who was Guyger’s patrol partner, testified Monday as she continues to stand trial for allegedly murdering Jean inside his apartment, claiming she thought she was in her own unit and that he was an intruder.

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Martin Rivera

During opening statements on Monday, prosecutors showed the jury sexually-explicit text messages between Rivera and Guyger that were sent hours and minutes before the shooting.

Prosecutors also said those messages between the two were deleted a day after Jean was killed. The messages were later recovered.

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It was also revealed by prosecutors that Guyger had sent Rivera texts while she was on the phone with 911 after she shot Jean.

Rivera received a text from Guyger, “I need you. Hurry” at 10:02 p.m. A minute later, Guyger sent a text that read, “I f***ed up.”

Rivera was also on the phone with Guyger three minutes before the shooting, and he claimed they were talking about work. “To the best of my recollection I remember asking about the suspects to see if they ever confessed and I really don’t remember a whole lot about the conversation,” he said during his testimony.

Now, activists with Mothers Against Police Brutality are calling for Rivera to be fired from the Dallas Police Department, saying that he “destroyed evidence” and that he should held accountable.

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Activists with the Next Generation Action Network are also wanting Rivera fired.