A Boston woman will not be charged after four of her babies were found dead in a freezer.

Police have been investigating the case since the bodies of four infants—two male and two female—were discovered frozen solid in shoe boxes wrapped in tin foil within a South Boston apartment back in November 2022, according to an April 30 press release from the Suffolk District Attorney Kevin Hayden.

DNA testing determined that all four siblings were the biological children of Alexis Aldamir, 69, and an unnamed man who died in 2011. Aldamir had purchased the South Boston apartment in October 1983, and worked at accounting firm in the city from 1980 until October 2021.

All the babies were full term (between 37 and 40 weeks of gestational age) and had no signs of trauma or injuries, per the release. The medical examiner said there is no method to determine how long the babies had been frozen and investigators were not able to establish their cause of death, which is listed as "undetermined."

"This investigation, which is one of the most complex, unusual and perplexing that this office has ever encountered, is now complete," District Attorney Hayden said in a statement. "While we have some answers, there are many elements of this case that will likely never be answered."

"We will never know exactly where or when the four babies found in Alexis Aldamir's apartment were born," Hayden continued. "We will never know if the four babies were born alive, and we will never know exactly what happened to them. We will never know how Alexis Aldamir concealed her pregnancies, or why she chose to do so." 

Authorities said they were able to locate Aldamir at a residential healthcare facility and question her about the tragic case. However, the woman "appeared confused and demonstrated a lack of understanding about where she was and who she was speaking to," per the press release. She ultimately wasn't able to provide any significant information.

The District Attorney's office decided not to charge her with any crimes because, in order to file charges for a homicide, they would need evidence that the victims had once been alive and would also need their cause of death determined, according to officials. And based on her cognitive ability, investigators don't believe Aldamir would be able to stand trial.

Additionally, they could not file charges against the father since he is no longer alive. 

There were no records of Aldamir giving birth to the four children, according to the office. She and the same father did, however, welcome a baby girl in April 1982, who they gave up for adoption, per paperwork obtained by authorities. Investigators added that none of Aldamir's coworkers at the accounting firm ever knew she had been pregnant at any point.

The infants' bodies were only discovered in November 2022 after a man and his wife found them while cleaning out his sister's apartment and called 911. 

E! News was not able to locate a lawyer on file to speak on Aldamir's behalf.