Rebecce Kay Park Fiancé and Sister in Jail After Body Disocvery

A body matching the description of missing woman Rebecca Kay Park was discovered on Tuesday, Nov. 25, a spokesperson for the Michigan State Police tells PEOPLE.

Park, 22, had not been seen since just before midnight of Nov. 3, and a massive search effort had been underway to locate her, with family members appearing on local news programs to spread the word.

There was an added sense of urgency to these efforts because Park was 38 weeks pregnant at the time she went missing.

Among the family members who were vocal in asking for help in locating Park were her fiancé, Richard Falor, and her younger sister Kimberly.

Falor suggested in an interview with WWTV that on the day Park vanished, an unknown person picked her up from her mother’s home and took her away in a car.

Shortly after the discovery of the body, Falor, 43, was booked into the custody at the Wexford County Jail at 7:30 p.m. EST, according to custody records obtained by PEOPLE.

A few hours later, shortly after midnight on Wednesday, Nov. 26, Kimberly Park, 21, was booked into the same jail.

The reasons for the arrests have not yet been disclosed, and it is not clear whether they relate to Rebecca’s disappearance or death. There are no charges listed for either Falor or Kimberly at this time.

Want to keep up with the latest crime coverage? Sign up for PEOPLE’s free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases.

Park’s phone had been found near her mother’s house; her body was found in Manistee National Forest, MSP said.

Officials declined to say if the remains of a newborn were also discovered or if the victim was or had been pregnant.

Park had been due to give birth Nov. 18.

The Wexford County Sheriff’s Office declined to comment further, pending an autopsy.