Six people, including a 15-year-old, who said they were members of a religious group called “Soldiers of Christ” were arrested after police said they found the remains of a woman who’d been beaten and starved.

Eric Hyun, 26, Gawom Lee, 26, Joonho Lee, 26, Juoonhyum Lee, 22, Hyunji Lee, 25, and the teenager are suspected of false imprisonment, tampering with evidence, concealing the death of another, and murder after the woman was discovered in the trunk of a car parked outside of a spa on Tuesday night, the Gwinnett County Police Department in Georgia announced on Thursday.

Speaking at a press conference, Cpl. Juan Madiedo said detectives believe that the woman was in her 20s or mid-30s and had come to the U.S. from South Korea over the summer to join the group. Authorities have not released her name as they attempt to first contact her family.

Madiedo said she weighed only 70 pounds, adding that medical examiners believe malnourishment contributed to her death.

Detectives believe that Hyun parked the car that held the woman’s body in the lot earlier that day, then called a family member to pick him up to take him to an Atlanta-area hospital to treat injuries unrelated to the death, Madiedo said. When the family member returned to the car to pick up a personal item, they looked in the trunk and called 911, authorities said.

According to Hyun’s arrest warrant, the woman’s body had been burned and wrapped in a blanket before being placed in the trunk.

Madiedo added that investigators believe the woman’s body had been in the car for a few days.

Authorities then searched a home in Lawrenceville belonging to the Lees and where they said Hyun had visited and previously lived. The suspects have “family ties,” police said.

“We do believe that the basement of the location was where these individuals did the beatings and kept the victim there until she passed away,” Madiedo said.

Authorities added that they believe the woman had experienced the beatings and malnourishment for weeks before her death. Madiedo said investigators don’t believe she was sexually assaulted.

With their shared religious affiliation, the suspects also face charges accusing them of being associated with a criminal gang.

It’s unclear whether or not they are represented by attorneys. The Gwinnett County District Attorney’s Office said a court date has not yet been scheduled.