The woman, who is in her 25s, was reported missing on Monday and since then an intensive search operation has been underway in Grästorp.
The police have searched the area with patrols, dogs and helicopters, but so far the search has not yielded any results.
The non-profit search organization Missing People has been called in to assist the police in the search, and began work on this on Friday.
An arrested
A man in his 40s has been in custody since Tuesday on suspicion of involvement in the disappearance.
The man is suspected for probable cause, and the prosecutor has until 12 o'clock on Friday to submit a request for arrest to the court, otherwise the suspect will be released on bail.