While Cape May County authorities haven't confirmed the dead body they found Monday is a missing 15-year-old girl, family members told 6ABC they have no doubt.

"We heard from people that this was the last house she was seen in, she was hanging out with friends and stuff," Nicole Angstadt's older sister, Heather Bradley, told the station.

The report said police remained at a "very active crime scene" Tuesday. It also quoted neighbors saying local teens had been using the property as a hangout since its owner died over the summer.

Cape May County Prosecutor Robert L. Taylor and Middle Township Police Chief Christopher Leusner said Tuesday the body of a white female was found at 100 Vermont Ave., in the Rio Grande Section of Middle Township. An autopsy was scheduled for Tuesday to help identify the female and determine how she died.

The authorities said detectives went to the vacant property as a result of a missing person investigation regarding Angstadt, who was reported missing by her mother on Dec. 1. But the statement did not indicate whether authorities believe the person they discovered to be Angstadt.

They're asking anyone with information to contact the prosecutor’s Office at 609-465-1135, the Lower Township Police at 609-886-2711 or the Middle Township Police Department at 609-465-8700, or to text TIP MTPDTIPS followed by a message to 888777.

According to an alert issued last week, Angstadt was last seen Nov. 29. She was described in the alert from Lower Township Police as a "15 year old runaway from the Erma section of Lower Township." She was wearing a black zip up sweatshirt, leggings and tan Ugg boots. She is described as being 5 feet and 8 inches tall, and 177 pounds. She has blonde hair with blue eyes.

She has been located in the past in the Rio Grande and Wildwood areas, police said at the time.

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