An Alaska woman charged with killing her two infant daughters -- the first in 2015 and the second in November -- scoured the internet for ways to kill without getting caught, according to police.

Stephany Elizabeth LaFountain, 23, of Fairbanks, is charged with one count of first-degree murder and two counts of second-degree murder in the death of each girl, according to Fairbanks police officials. Her arrest Thursday was the culmination of a nine-month investigation prompted by the death of her second daughter, identified on social media as Jasmine Rose LaFountain.

Court records show the second-degree murder charges include one charge for each child of murder with the intent to cause serious injury and murder with extreme indifference. LaFountain has no other children.

"This is just an unimaginable tragedy," Fairbanks police Chief Eric Jewkes said Thursday night during a brief news conference on LaFountain's arrest. "We have two infants, we have two babies, that were killed by their mother. How do we even imagine that?"

Investigators said LaFountain called 911 just before 6:30 p.m. Nov. 20 and said her 13-month-old daughter was not breathing. As paramedics responded to her home on the Fort Wainwright military base, LaFountain also called her husband’s family, who arrived a few minutes later.

A GoFundMe page set up to help the baby's father, William "Billy" LaFountain Jr., with funeral expenses, indicated the girl's paternal grandparents lived on the base. Her grandfather performed CPR until paramedics arrived.

The baby’s father, who was serving in Iraq at the time, was also contacted and was able to return home on emergency leave.

Jasmine, referred to in the police news release only as J.L., was rushed to Fairbanks Memorial Hospital and later flown to Providence Medical Center for treatment. The GoFundMe page said she was pronounced brain-dead two days later.

She was removed from life support Nov. 24, after her father arrived, and died in his arms, the fundraising page said.

The page described “Jazzy” as a “priceless treasure that brought so much love and joy into (her family’s) lives.”

Fort Wainwright police investigators began the initial investigation into Jasmine's death, but turned it over to Fairbanks detectives because LaFountain and the baby were not military personnel, the department's news release said.

During the investigation, detectives learned that LaFountain, while in a previous relationship in 2015, had a 4-month-old daughter who died under similar circumstances, though the baby’s death was not investigated at the time as a homicide.

"As detectives reviewed the 2015 FPD case, they found similarities to the 2017 case, which broadened their investigative scope," Fairbanks police officials said in the news release.

In the 2015 case, LaFountain, then known by her maiden name, Stephany Bilecki, called 911 on Sept. 15 to report her baby was not breathing. As in the more recent case, paramedics responded to her apartment and took the baby to Fairbanks Memorial.

The baby, identified in the news release as C.P., was pronounced dead about an hour after the 911 call. The GoFundMe page for Jasmine identifies her half-sister as Chyanne.

Chyanne's obituary identifies her as Chyanne Rose Peryea. LaFountain shared photos of the infant on her Facebook page, listed under the name Liz Bilecki. 

"She touched so many lives during her short time here and brought so much happiness and love with her presence," Chyanne's obituary said. "The way she touched the hearts around her will never be forgotten or diminish with time."

During the homicide investigation following Jasmine’s death, a forensic analysis of Stephany LaFountain’s computer showed internet searches about how to kill someone without getting caught, the news release said. Some of the searches included:

Ways to suffocate,

Best ways to suffocate,

Ways to kill human with no proof,

Can drowning show in an autopsy report,

16 steps to kill someone and not get caught,

How to commit the perfect murder,

Drowning and forensics, and

Suffocating and smothering.

Police officials said autopsy results showed Jasmine died of a lack of oxygen to the brain.

The cause of her sister's death in 2015 was listed as undetermined, but the symptoms were consistent with suffocation, Fairbanks police officials said.

Jewkes said Thursday that the public was not made aware of investigators’ suspicions prior to LaFountain’s arrest.

"What we know and what we want to pass on in law enforcement is that there is the work you see, and there's the work you don't see," Jewkes said. "This is a prime example of the work that you don't see."

The police chief said thousands of hours went into the investigation.

“It was just incredible,” Jewkes said.

Jewkes thanked the LaFountain family for their patience and trust during the investigation.

"We have the family of a baby that has suffered in obscurity, in silence, that no one knew," the chief said. "They were all alone in this whole process. No one knew about it. That's a tough situation to be in.

“They shouldered the grieving process alone, and we’re going to bring this to light and hopefully provide some kind of closure to them. And that’s important.”

An update posted Monday on the family's GoFundMe page thanked the agencies, healthcare workers and experts who have worked on behalf of both Jasmine and Chyanne. The statement called the investigation "exhaustive and meticulous" and said it was done "with the utmost respect for the LaFountain family."

"It has been a difficult process for the family who are only seeking to give a voice to two murdered children," the statement said. "They appreciate everyone's sympathies, prayers, and healing words as the process moves forward."

Billy LaFountain filed for divorce from his wife about a month after their daughter died. The uncontested divorce was granted in February, court records show.

Stephany LaFountain's bail has been set at $2 million, The Washington Post reported. If convicted of first-degree murder, she faces up to 99 years in prison on each of those charges.