Woman Accused of Killing Mom-to-Be Because She Wanted Baby Is Now Charged in Fetus' Death

The Missouri woman accused last year of kidnapping and killing a pregnant woman to steal her unborn baby has now been additionally charged in connection with the death of the mom-to-be's unborn child, authorities announced.

Amber Waterman, 43, and her husband, Jamie Waterman, 43, were charged in a superseding indictment returned by a federal grand jury on Tuesday, which alleges Amber caused the death of the baby in utero.

The U.S. Attorney’s Office for the Western District of Missouri alleges that Amber lured Ashley Bush, who was 31 weeks pregnant at the time, killed her, and then attempted to cut her baby out of her abdomen.

Amber allegedly used a fake Facebook profile under the name “Lucy,” through which she offered the expecting mother free baby clothes. They later met up a second time outside a convenience store in Maysville, Ark., after Waterman allegedly offered Bush a purported job using the fake social media identity and then kidnapped her, federal authorities say.

Federal complaints obtained by PEOPLE last year stated that Jamie allegedly told detectives his wife confessed to killing Bush, and that the couple later burned her body and dumped it in a remote area. The affidavits alleged Jamie led police to the place where they had dumped Bush's charred remains.

Police believe that Amber shot Bush and cut the baby out of her abdomen. The baby did not survive and was dumped in a different location. Amber, in an interview with police, claimed she delivered a stillborn baby the same day Bush went missing.

"This is just a reminder that there is evil in the world," Prosecuting Attorney Nathan Smith said last year. "People do evil things. That someone would prey upon a pregnant woman at her most vulnerable state is unimaginable. That's the world we live in."

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In an updated indictment Tuesday, the U.S. attorney’s office charged Amber with being responsible for the child’s death, as well as Bush’s. The Missouri woman still faces federal charges for the fatal kidnapping, while her husband Jamie is still charged with assisting his wife and trying to prevent her arrest.

The couple is still in federal custody, the U.S. attorney’s office said this week. The Watermans have pleaded not guilty to the charges, according to NBC News.

Amber faces life in prison, while Jamie faces a maximum sentence of 15 years.