LATEST: In a probable cause statement police say accused murder mom admits she killed 6 out of 7 infants found dead. The 7th was a stillborn, police say. 

Earlier: Cops say a Utah woman has been arrested on six counts of murder after authorities found the bodies of seven infants packed into separate cardboard boxes at a home.

Police arrested Megan Huntsman, 39, following a gruesome discovery at a residence where the accused formerly lived until she moved out in 2011.

Officers responding to a tip phone call from a family member who is currently living at the Pleasant Grove residence arrived at the home to find the first baby which "appeared to be a full term," according to a police statement.

"A family member was cleaning out the garage and came across a box that looked suspicious. Upon opening the box they found the infant inside," Capt. Michael Roberts of the Pleasant Grove Police Department told ABC News.

Law enforcement obtained a search warrant to inspect the home. They discovered six more infant corpses, packaged in separate containers, the police statement said.

Capt. Roberts say investigators believe Huntsman gave birth to the six other babies between 1996 and 2006 and murdered them.

Police arrested Huntsman and booked her at the Utah County Jail on six murder counts, but did not elaborate on why she was not charged with seven counts.

Capt. Roberts could not confirm whether Huntsman had any other children or if she was married.

"It's still an ongoing case so we're still working on some information we've received," Roberts said.