Updated

A missing persons group says it is skeptical of a 19-year-old woman's claim that she has killed more than 20 people -- most of the murders taking place in her native Alaska and so many that she "stopped counting at 22."

Seeking Alaska's Missing, a statewide support group for missing people and their families, said Tuesday that it is "skeptical" of alleged killer Amanda Barbour's claim that she took part in the murder of at least 22 people as she traveled south from Alaska to North Carolina and was involved in a satanic cult.

Barbour, 19, and her husband, Elytte Barbour, 22, are charged with first-degree murder in the November killing of 42-year-old Troy LaFerrara in Sunbury, Pa. Prosecutors allege that Miranda Barbour met LaFerrara on Craigslist and offered him sex for $100. After luring LaFerrara into her vehicle, Miranda Barbour stabbed him, while her husband of three weeks strangled the man from the backseat of the vehicle.

In a shocking jailhouse interview, Miranda Barbour allegedly told The Daily Item in Sunbury that she had previously killed at least 22 people from Alaska to Texas, and could "pinpoint on a map" where the bodies could be located.

In the case of LaFerrara, Barbour said she and her husband killed him because, "he said the wrong things," according to the newspaper's report published Saturday. Barbour allegedly said she would have let LaFerrara go, but after telling him she was just 16, he said he wanted to proceed with the arrangement the two had made.

"If he would have said no, that he wasn't going to go through with the arrangement, I would have let him go,'' she said, according to the newspaper.

Barbour allegedly told the paper Friday that most of the other crimes took place in her native Alaska -- a claim the missing persons group questions -- and said she took part in the killings as early as 13 years old.

"Based on the research we have conducted, we are not putting much stock into what this woman has claimed. We remain skeptical at this time until further proof is given," the group said in a statement to FoxNews.com. "Our focus at Seeking Alaska's Missing is finding the missing and, unless they have not been reported by a family member or friend, the numbers simply do not match up."

The FBI confirmed to FoxNews.com that it is investigating the young woman's claim, but declined to elaborate further on the case. The agency said in a statement Sunday that its Philadelphia division "has recently been in contact with the Sunbury Police Department regarding Miranda Barbour, and will offer any assistance requested in the case.''

Barbour, originally from North Pole, Alaska, lived in Anchorage and Palmer before leaving the state. The young woman claims she was part of a satanic cult that took her to several other states, including California, Texas and North Carolina.

Barbour could face the death penalty in connection with LaFerrara's murder if she is convicted.