BROOKLYN - Police say the baby whose body was found in a bag of a Brooklyn teenager caught shoplifting was born alive and then asphyxiated.

The NYPD has not released information about how this was determined. The medical examiner's office says the initial autopsy could not determine the cause of death.

According to police, 17-year-old Tiana Rodriguez told officers she was carrying the fetus because she had delivered the baby the day before and didn't know what to do.

Detectives say Rodriguez and a friend were stopped by a security guard at a Manhattan Victoria's Secret store. The guard searched one of the girl's bags and made the discovery.

Both teens have been arrested on charges of petit larceny and possession of stolen property. The girl believed to have given birth was hospitalized, and the other questioned by police.

Authorities say more serious charges could be filed.