Detectives investigating a serious assault on a 17-year-old girl in Shearer Road on Monday April 11 have been granted an extension to continue questioning a 28-year-old man from Portsmouth
Officers have until the early hours of the morning to question the man over the incident.
Hampshire Police said the attack took place at a property in Shearer Road in the city with possible links to the sex trade. Police have since been back to the property five times and carried out searches. The woman who living in the property has been moved into Police protection to an undisclosed location.
Officers also gave advice on personal safety to sex workers via charities and support groups after it happened.
A Hampshire Police spokesman said: "Police investigating a serious assault on a 17-year-old girl in Shearer Road, Portsmouth, on Monday, April 11 have made an arrest.
"A 28-year-old man from Portsmouth is in police custody."
Detectives' hunt for the person responsible saw them make an appeal at the League Two game between Portsmouth and Wycombe Wanderers last Saturday.
They also offered a £5,000 reward for information.