A Utah mother accused of slaying six of her own infant children over the course of a decade secretly gave birth to each of the babies without medical assistance at home and then immediately killed them, police said on Wednesday.

Megan Huntsman, 39, was ordered to be held in lieu of $6 million bail on Monday on suspicion of murdering six newborn babies whose bodies were found rolled up in shirts, towels and plastic bags and stashed inside separate cardboard boxes in the garage of her former home.

Police in the Salt Lake City suburb of Pleasant Grove say Huntsman has admitted under questioning that she strangled or suffocated the six babies just after they were born in a rare case of serial infanticide that ran from 1996 to 2006.

The body of a seventh infant born during the same period and disposed of the same way also was found in the garage, but police say they believe that child was stillborn.

Police disclosed new findings in the case as medical examiners continued autopsies on the remains and DNA tests aimed at confirming such details as the manner and cause of death, their parentage and their genders.

Following extensive interviews with neighbors and family members, including Huntsman's three older children - all daughters, now aged 20, 18 and 14 - investigators say the mother somehow managed to keep nearly a decade of consecutive pregnancies a secret.

"We have not found anybody who has ever suspected that she was pregnant," Pleasant Grove police Captain Mike Roberts said. "All seven were born in the home," Roberts said.

Reuters