Missing Texas teen Savanah Nicole Soto, who was due to give birth any day, and her boyfriend have been found dead following a multi-day search, a family member confirmed Tuesday.

Soto and her boyfriend Matthew Guerra, who was also reported missing, were found dead inside a vehicle, a family member told CBS San Antonio affiliate KENS 5.

The Leon Valley Police Department earlier told CBS News that Soto, 18, was reported missing by her family and was last seen on Friday, Dec. 22, a day before she was scheduled to be induced.

At a briefing Tuesday evening, police confirmed that two people were found dead in a car they described as Guerra's, but they did not confirm the identities or provide any details about the cause of death. 

San Antonio Police Chief Bill McManus said the department was dealing with a "very, very perplexing crime scene" and looking into the possibility of homicide, but he could not say for sure how either person died.

"We believe it was the missing woman and her boyfriend but we can't confirm that" until the medical examiner completes the examination, McManus said. He also would not confirm whether or not the woman who was found was pregnant, again saying that would be for the medical examiner to determine.

McManus said the car might have been at the location where it was found "possibly for three or four days."

Soto's family informed police about the car after they were alerted by someone who came across the vehicle, and they were devastated by the outcome of the search.

"I just want answers to who, what and why — why did this happen to her?" her grandmother, Rachel Soto, told KENS. In tears, she thanked people for their prayers and support.

Soto's family previously told KENS that she was set to be induced on Saturday night and was a week past her due date. Police confirmed to CBS News that Soto had missed an appointment. 

On Monday, the department issued a CLEAR alert, which are sent out for missing, kidnapped or abducted adults who are in immediate danger, according to the Texas Department of Public Safety. The CLEAR alert said that Soto, who is 5'1" and has brown hair and eyes, was last seen at around 2 p.m. on Dec. 22. The alert said that she might be in a gray 2013 Kia Optima with temporary Texas tags. 

KENS reported that the address where Soto was last seen was the apartment complex where she lived with her boyfriend, the father of her child. According to Soto's family, no one had been able to contact the boyfriend since Soto disappeared. 

Rachel Soto said her granddaughter was excited to welcome her baby and had a nursery decorated and a name picked out. The teen was expecting a baby boy, her grandmother said. 

"She was thrilled and excited about being a mom. ... I pray to God every day, every minute, every second of the day we pray to God to bring her home, to bring her home safely because we need her home, to complete our family again," she said.

KENS reported that police attempted to enter Soto's apartment on Monday, but were unsuccessful. Soto's friends and family organized a search of the area on Monday night, and Soto's family told KENS they were planning a second search of the area Tuesday.

Soto's grandmother said the family just wanted the teen safely returned. 

"It's not normal, something's not adding up here ... I want answers, we all want answers," she said. "She's a beautiful girl ... She'll help anyone and I want someone to help us."

In:
• Texas
• Missing Woman
• Missing Teen
• Missing Person

Kerry Breen

Kerry Breen is a reporter and news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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