Authorities in Michigan are intensifying their search efforts for a pregnant woman who has been missing since Monday.

Rebecca Park, 22, was last seen willingly entering the passenger seat of a dark-colored sedan near a relative’s residence in Boon Township. Prior to her disappearance, Park mentioned she was expecting someone to pick her up, though the individual driving the vehicle was not identified by witnesses, as reported by the Cadillac News.

As Park is 38 weeks pregnant, her situation is considered critical. The identity of the person she left with remains unknown.

The Cadillac News also noted that Park’s cellphone was discovered on a road close to the location where she was last spotted.

Rebecca Park is described as being 5 feet, 2 inches tall and weighing around 140 pounds. Anyone with information on her whereabouts is urged to contact the Wexford County Sheriff’s Office at 231-779-9216.

[Feature Photo: Wexford County Sheriff’s Office]