Megan Huntsman's mug shot
Utah County Sheriff
Residents of Pleasant Grove, Utah, expressed shock Monday that a neighbor of 15 years – who had babysat their children and grandchildren – admitted to killing six of her own babies
"She always seemed perfectly normal, very friendly," says Aaron Hawker after Megan Huntsman, 39, was charged with six counts of murder in the deaths of the babies born between 1996 and 2006.
Huntsman's estranged husband, Darren West, was cleaning out the garage when he found the remains of a baby sealed in a plastic bag in a sealed unlabeled cardboard box, Pleasant Grove Police Chief Mike Smith tells PEOPLE.
"He called Megan and she admitted she had killed the child. Then he called police," Smith says.
Inside other boxes investigators found six more remains of babies. Six of the seven are believed to have been killed by strangulation and one appeared to have been stillborn, says Smith. Huntsman "confessed" to the killings, he says.
Huntsman moved out about two years ago and is living with a boyfriend, police say. Her estranged husband "says he knew nothing about this," says the police chief; West has not been arrested or named a person of interest.
But questions remain.
"Most people don't know how you don't notice seven pregnancies," says Smith. "It's one thing to conceal it to the outside world and a more difficult thing to conceal from your loved ones. So we'll have to continue to investigate that."
Huntsman has three surviving daughters, two believed to be teenagers and one believed to be about 20, who had been living in the house, according to Smith.
The youngest daughter would have been born in the middle of the other pregnancies. "Why did this girl live?" asks Smith. "We'll continue to try and find an answer to that one."
Neighbors in this community 35 miles south of Salt Lake City, meanwhile, also remained baffled.
"She babysat our grandkids about 10 years ago. That's how much we trusted her," says Hawker. "We [are] all looking at each other saying, 'Pregnant seven times and we didn't know?' ... She fooled everyone, no question."
Reporting by CATHY FREE