KALAMAZOO, Mich. (WOOD) — Authorities believe there was foul play involved in the disappearance of a Portage mother earlier this month.

In a press conference Monday at the Kalamazoo County Sheriff’s Office, authorities said that while they could not reveal much information in the search for 35-year-old Heather Kelley, they did find evidence in her car that led them to think foul play was involved.

Kelley, a mother of eight from Portage, was last seen on Dec. 10 when she left her home around 9 p.m. that night. According to a missing poster on the sheriff’s office’s Facebook page, Kelley spoke to her kids by phone at 10:20 p.m., telling them she’d be home shortly. She never returned.

Her car was found abandoned in Comstock Township a few days later.

Police are still investigating her whereabouts.

A person of interest in the case is currently being interviewed by detectives. Authorities did not say how the person of interest was linked to Kelley’s disappearance but they did disclose that they were being held in custody at this time on unrelated charges.

Kelley is described as 5’10”, 130 pounds with long blonde hair.

If you have any information on Kelley’s whereabouts, you’re asked to contact KCSO at 269.383.8821 or Portage Public Safety at 269.329.4567.