Rockland authorities say an 18-week-old human fetus was found in a sewer Monday in Nanuet. 

Investigators say a county worker was skimming a catch drain and at first thought the remains were a doll when they made the discovery at the Pascack pump station in Nanuet. 

Rockland Sewer District Executive Director Mike Saber says the sheriff’s office was contacted right away. 

“This is the first in 30 years that I’ve been here that we’ve come across something like this,” said Saber. “We don’t expect to see this. It’s happened across the country but hasn’t happened here.” 

Officials confirm an investigation is underway and that the fetus’ gestation was confirmed by the medical examiner. 

Since the fetus was only a little more than 4 months, it would not be considered old enough to survive outside of the mother’s womb. 

So far, it's not clear if the mother miscarried or if the incident involved a crime. 

News 12 is also unable to determine if there's a state law requiring that fetal remains are disposed of in a certain way. 

News 12 reached out to the Rockland County Sheriff’s Office and state Health Department to confirm. 

A law enforcement source tells News 12 authorities would want to speak to the mother to make sure she wasn’t harmed by someone who may have caused her to miscarry.   

Sewer district officials say the pump station serves the Nanuet and Spring Valley area. 

They say the station is checked daily and that the fetal remains were likely discarded the same day they were found. 

Anyone with information about the case is asked to call the Rockland County sheriff’s confidential tip line at 845-638-5466.