Woman locked up by her boyfriend in a box for 4months.

A Missouri woman claims that she escaped from her house Thursday after being held captive in a box by her boyfriend for the past four months.

Police said the suspect had allegedly been locking the victim in the box while he went to work since January. After searching the house in question, "officers did observe a large wooden box consistent with what the female described," Sedalia Detective Sgt. Joshua Howell said in a statement Friday, according to The Washington Post.

Police are currently searching for 47-year-old James Barton Horn Jr., who had fled the area by the time officers arrived. Authorities located his vehicle on Thursday evening, but as of now he remains at large.

The alleged victim, who is not being identified, escaped Thursday and ran to a neighbor's house, where she dialed 911. Howell described her as sounding "hysterical" on the phone, though she later appeared calm once officers responded to her call. In a news conference Friday morning, Sedalia Police Department Chief John DeGonia said she seemed "physically okay."

Howell stated that police trust the woman's story because "what she told us is exactly what we found," the Sedalia Democrat reports.

DeGonia added that the relationship was initially consensual before it "eventually led to 'you can't leave.' "