Over a decade beginning in 1996, Megan Huntsman gave birth to at least seven babies in her home at Pleasant Grove, Utah. One died at birth and the other six were strangled or suffocated, their bodies concealed in boxes that were stored in the garage, she told police, according to documents released by state authorities Monday.

Huntsman, 39, was being held on $6 million bail - $1 million for each of the babies she is accused of killing - after a preliminary court appearance Monday, a spokesman for the Utah County jail told the Los Angeles Times. Formal charges are expected by next week, according to the Utah County prosecutors.

According to the probable cause affidavit released by authorities, Huntsman told police that she had given birth to "at least seven babies" between 1996 and 2006. Each body was "wrapped in either a towel or a shirt, placed inside of a plastic bag, and each was contained in a separate cardboard box" all stored in the garage.

No motive is described in the court papers. Nor does the statement deal with how Huntsman was able to avoid any questions from neighbors or her older children about her pregnancies.

According to the affidavit, police on Saturday responded to a report that a dead baby had been found at the garage in Pleasant Grove, about 35 miles from Salt Lake City. The complaint had been filed by Darren West, Huntsman's estranged husband who had been convicted of drug-related charges.

Pleasant Grove Police Capt. Michael Roberts said officers believe West and Huntsman were together when the babies were born.

"We don't believe he had any knowledge of the situation," Roberts told the Associated Press.

Asked how West could not have known about the situation, Roberts replied: "That's the million-dollar question. Amazing."

When West confronted Huntsman, she admitted that the baby was hers and said it had been stillborn in 2006, according to the affidavit. West then contacted authorities.

"The baby was well preserved and appeared to be full term," according to the probable cause affidavit.