A pregnant Gwinnett County teenager was found dead in a wooded area by family members early Monday morning, authorities said.

Police officers could not determine the 16-year-old’s manner of death at the scene, but the following day, the Gwinnett Medical Examiner’s Office conducted an autopsy and ruled her death a homicide. Police identified her as Mia Campos. She was seven months pregnant, her family told Univision Atlanta. The baby would have been named Sebastian.

“She was just lying there ... already cold,” her mother, Miriam Zarate, said of how they found Mia’s body in a wooded area near the 3600 block of Stephens Road near Loganville.

“I touched her belly, trying to, hoping that maybe her baby would still be alive, but too much time had passed,” Zarate told Univision in Spanish through anguished tears. “There was nothing we could do.”

The teen was eagerly preparing for her baby shower and was even making her own party favors, her mother told the news station.

“She was a sweet, innocent girl,” Zarate told Univision. “She was so excited to meet her baby.”

On Wednesday, officers arrested Campos’ ex-boyfriend, Jesus Monroy, and accused him of making false statements to an officer, police said. Officials did not say if the 20-year-old was considered a person of interest in Campos’ death.

Monroy was booked into the Gwinnett jail Wednesday on one felony count and remains there without bond, online records show.

The case began Sunday night, when Campos’ family members told police the teen had left the house with an unknown person. When she did not come home, her family used a cellphone app to track her location to where she was found, police said.

Detectives and investigators from the medical examiner’s office were called to the scene, where they gathered evidence and spoke to witnesses, according to police. It was not until Tuesday that the ME’s office determined that Campos’ death involved foul play. Police did not share her cause of death.

Zarate told Univision that she was shocked at the news that Monroy had been arrested at all.

“I don’t understand because he was here that night. He helped us look for her. He found her. He came here on Monday, and he was here last night (Tuesday),” she said. “I don’t know what happened.”

Zarate created a GoFundMe page to raise money for funeral expenses.

“With all my heart, I ask you for help to give her and her baby a dignified burial,” she wrote on the fundraising page.

The investigation remains active, and police are asking for assistance from the public. Anyone with information is asked to contact Gwinnett police detectives at 770-513-5300. To remain anonymous, tipsters may contact Crime Stoppers at 404-577-TIPS (8477) or visit www.stopcrimeATL.com. Crime Stoppers tipsters can receive a cash reward for information leading to an arrest and indictment in this case.