By Christina Hager

MARLBORO (CBS) – Karla Rodriguez’s mother wept as her daughter’s alleged killer walked into Marlboro District Court. Some relatives wore shirts that said, “#Justice4Karlita”.

“Really good human being,” said her cousin Isabel Famania-Banks. “She was taken from us too soon.”

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Police found the 20-year-old pregnant mother gunned-down in her car in Hudson Thursday. Prosecutors say her boyfriend of three months, Luis Santos, was caught on security video shooting her windshield as she pulled out of his driveway.

Luis Santos in court Monday. (WBZ-TV)

Her mother told police Rodriguez was pregnant, and that her relationship with Santos “began to deteriorate after they learned of the pregnancy.”

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On the day of the murder, Rodriguez called Santos for a ride from a medical appointment in Worcester, and during her ride back to Hudson, her mother told police she sent a series of frightening texts. She said, “Santos was very mad.” She texted that he “told Rodriguez that he was going to kill her…” Finally she texted that “Santos tried to hit her.”

Karla Rodriguez (Image Courtesy: Giallyssa May Ortega)

Minutes after the texts stopped, Santos’ friend says he got a call. “Mr. Santos did indicate to that person, ‘I need help. I need help.’ He was asked, ‘What did you do?’ At that point the defendant said, ‘I killed Karla,’” said Prosecutor Joseph Gentile. “He was at that point asking the witness for help attempting to get a flight to Puerto Rico.”

Karla Rodriguez leaves behind a 10-month-old boy. “We just want people to voice, you know if they’re in a bad situation, speak up,” said Famania-Banks. “Say something.”

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Not guilty pleas were entered on behalf of Santos, who’s being held without bail. His next court appearance is scheduled for January 24th.

Christina Hager