Four family members were sentenced to life in prison in a federal terrorism and kidnapping case that started as an investigation into a 3-year-old boy who went missing from Georgia and was found dead at a New Mexico compound in 2018, the U.S. Department of Justice announced Wednesday.

Authorities arrested five adults and put 11 children into protective custody in 2018 after the boy's body was discovered in a SWAT raid at a squalid compound in northern New Mexico. The boy, identified as Abdul Ghani, was abducted by his father, Siraj Wahhaj, and other members of his family who believed the boy would be resurrected as Jesus Christ.

Prosecutors accused the family of engaging in firearms and tactical training to prepare for attacks against the government. "The group intended to use the child as a prop in a plan to rid the world of purportedly corrupt institutions, including the FBI, CIA, and U.S. military," the Department of Justice said in a news release Wednesday.

Siraj Wahhaj, his sisters, Hujrah Wahhaj and Subhanah Wahhaj, and Subhanah’s husband, Lucas Morton, were sentenced Wednesday to life in prison without the possibility of parole. The fifth defendant — Jany Leveille, a Haitian national — was sentenced to 15 years in prison under the terms of her plea agreement.

"All of the children are all of our children, and loss of any child is a loss to us all," U.S. Attorney Alexander M.M. Uballez said in a statement. "The horrifying events of 2017 and 2018 played out in graphic detail during this trial: from radical ideologies to violent extremist beliefs, the banality of everyday life centered around the corpse of a dead child within a fortified compound in rural New Mexico."

Airport attack, police stations on fire:Mass prison escape brings chaos in Haiti

3-year-old boy died just weeks after arriving in New Mexico

Abdul was abducted from his mother in Georgia in December 2017, according to court records. The boy was transported to a remote property in Amalia, New Mexico, near the Colorado state line.

The four family members were led by Leveille, described as a spiritual leader for the group, who prophesied that Abdul was going to resurrect on Easter, which was April 1, 2018, at the time. The group believed that Abdul would then "lead the group to face society and kill those who did not join them," the Department of Justice said.

Prosecutors described the rural property as a compound that was heavily fortified, purpose-built, and militarized. In preparation for the Easter resurrection, the group increased its firearms and tactical training, according to court records.

When the Easter resurrection didn't occur, prosecutors said Leveille claimed that the boy would instead return around his birthday — Aug. 6, 2018 — or as Subhanah Wahhaj’s soon-to-be-born child. About three days before Abdul's birthday, authorities conducted a raid on the compound and found 11 children ranging in age from 1 to 15.

The children had been living in poor conditions and were discovered in various states of dehydration and emaciation, authorities said. Authorities also found firearms and ammunition that were used at a makeshift shooting range on the property in addition to training documents.

After a further search of the property, authorities located the remains of Abdul in an underground tunnel. The investigation found that Abdul died on Christmas Eve in 2017. An exact cause of death was never determined but prosecutors claimed that the boy, who had frequent seizures, had been deprived of crucial medication.

Pennsylvania beheading case:Pennsylvania man accused of beheading father charged with terrorism

Leader of group diagnosed with acute schizophrenia

Wednesday's sentencing comes months after jurors convicted the four family members in what prosecutors had called a "sick end-of-times scheme."

After a three-week trial last fall, a federal jury convicted Siraj Wahhaj of three terrorism-related charges. Morton was also convicted of terrorism charges, along with conspiracy to commit kidnapping and kidnapping that resulted in the boy’s death. Wahhaj’s two sisters were convicted on kidnapping charges.

During the trial, the defendants argued that the case was the product of “government overreach” and that they were targeted because they are Muslim.

Leveille, who had faced up to 17 years in prison under her plea agreement, was sentenced to 15 years since she has been receiving treatment for a diagnosis of acute schizophrenia that followed her arrest in 2018. She had pled guilty to conspiracy to provide material support to terrorists and possessing a firearm while unlawfully in the United States last August.

"The facts are so horrendous. But also with Ms. Leveille, this is the first time there has been any acceptance of responsibility" among the defendants, Judge William Johnson said. Prosecutors and Johnson noted that it was significant that Leveille took responsibility and apologized to Abdul's mother and her co-defendants.

Contributing: Trevor Hughes, USA TODAY; The Associated Press