A US woman accused of killing seven babies she gave birth to over a decade has been arrested after police discovered the tiny bodies stuffed in cardboard boxes in the garage of her former home.

Megan Huntsman, 39, who lived in the Utah home until three years ago, had the infants between 1996 and 2006, investigators said on Sunday.

Officers responded to a call on Saturday from Huntsman’s estranged husband about a dead infant at the home, police Capt Michael Roberts said. Officers then discovered the six other bodies.

Megan Huntsman, who was booked on suspicion of killing six of her newborn children.

Roberts declined to comment on a motive and what Huntsman said during an interview with investigators.

Neighbours in the middle-class neighbourhood said they were shocked by the accusations and perplexed that the woman’s older children still living in the home didn’t know their mother was pregnant or notice anything suspicious.

The spokesman said police believe the estranged husband and Huntsman were together when the babies were born, but the estranged husband isn’t a person of interest at this time. The man’s name was not immediately released.

“We don’t believe he had any knowledge of the situation,” Roberts said.

Asked how the man could not have known, Roberts replied, “That’s the million-dollar question. Amazing.”

The babies’ bodies were sent to the Utah medical examiner’s office for tests, including one to determine the cause of death. DNA samples taken from the suspect and her husband will determine definitively whether the two are the parents, as investigators believe.

Huntsman was booked on Sunday into the Utah County Jail on six counts of murder.

The house is owned by the husband’s parents, and the man was cleaning out the garage when he made the grisly discovery.

Huntsman’s three daughters still live there, long-time neighbour Sharon Chipman told The Salt Lake Tribune. The oldest are around 18 to 20 years old, while the youngest is about 13, she said.

Huntsman was a great neighbour, and Chipman trusted her to watch her grandson when he was a toddler, Chipman added.

“She took good care of him. She was good. This really shocks me,” Chipman told The Tribune.

Roberts said the case has been “emotionally draining” and upsetting to investigators. He was at the home when the bodies were discovered.

“My personal reaction? Just shocked. Couldn’t believe it. The other officers felt the same,” he said.

“They got more and more shocked each box they opened,” Roberts said.