MONTEBELLO ( — Montebello police say they have shot and killed a man wanted for the murder of his estranged wife, who was pregnant.

Investigators say 26-year-old Christopher Diaz had been on the run for weeks, wanted for the fatal shooting of his estranged wife, Roxann Acosta, August 6.

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Police say the couple had been spending time together for several days before they ended up at the home of Diaz’s mother in Montebello.

They say the couple got into an argument and witnesses heard gunfire erupt.  Diaz’s mother, who was in the house, said she had been in another room at the time of the incident.

Police say there were other people in the home when Diaz ran from the scene.

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Police tracked him using surveillance. A witness at the scene of Friday’s shooting said Diaz was being tailed by authorities and had jumped out of an SUV before gunfire erupted.

Acosta’s family says her baby was the child of a new boyfriend, not Diaz, who was a known gang member.

Her mother on Friday said the family can finally begin to heal.

“We just want justice for Roxann and we got it,” she said. “She was amazing, she was beautiful — a great mother.”

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