Detectives are investigating reports a vulnerable teenage girl has been forced into sex work over the past three months on Victoria's southwest coast.

A 33-year-old man was arrested after police searched a property in North Warrnambool over allegations concerning the activities of a 17-year-old girl, police say.

The man was interviewed about procuring and inducing a child to take part in sex work, allowing a child to take part in sex work, and living on the earnings of a sex worker.

But he was later released while detectives from the Warrnambool Sexual Offences and Child Abuse Investigation Team make further inquiries.

Detective Sergeant Chris Asenjo said detectives received information on Monday and were scouring social media as part of their investigation.