Neighbors Arrested, Newborn Baby Found Days After Woman, 22, Vanished While 8 Months Pregnant

North Dakota police investigating Savanna Lafontaine-Greywind's disappearance made the startling discovery Thursday.

The investigation into the disappearance of a young pregnant woman in North Dakota has led to a startling discovery.

Five days into their search for 22-year-old Savanna LaFontaine-Greywind, investigators reportedly found a newborn baby in her North Fargo apartment building on Thursday.

Watch: Remains of Missing Teen Discovered 10 Years After Disappearance

Family members told reporters the 2-day-old baby was healthy but taken to a hospital for tests. Police have not said conclusively whether the girl is LaFontaine-Greywind’s, though "our investigation thus far indicates the probability that this is Savanna Greywind’s child," they wrote in a statement.

The young woman remains missing.

"We do not have information that tells us where Savanna Greywind is," Fargo Chief of Police David Todd said in a Facebook video Thursday.

Todd said the baby was discovered while investigators executed a search warrant at "the suspects'" residence.

Those suspects have been identified as William Hoehn and Brooke Crews, who live in the same building as LaFontaine-Greywind.

Hoehn, 32, and Crews, 38, were detained and taken to the police department for interviews by detectives.

As further information was developed and evidence obtained, Hoehn and Crews were both arrested and charged with class A Felony Conspiracy to Commit Kidnapping.

Still, police said their investigation into the strange case continues.

Watch: Police Searching for 4 Young Men Who Went Missing Within Days of Each Other

"We’ve had 35 detectives, four sergeants, two lieutenants and a deputy chief working — in many cases, around the clock — on this investigation and we have also received assistance from local, state and federal agencies. We’ve also used K-9s, watercraft and several aircraft in this investigation," police said.