Croatian police were reportedly recovering a body from a cove just outside the city of Dubrovnik last night, near where Australian backpacker Britt Lapthorne had gone missing.

The identity of the person was unknown and it was yet to be confirmed whether it was male or female.

But the discovery comes amid a search for the 21-year-old Melbourne traveller. Ms Lapthorne was last seen in the early hours of September 18 at the city's Latino Club Fuego nightclub.

Yesterday, police left the recovery site a few hundred metres from the city centre bound for the main port where more police are believed to be waiting.

The recovery took place near a popular local swimming spot and in front of two major hotel resorts.

Police spokesman Ivan Kukrika said it was impossible to identify the badly injured body without forensic information.

''The remains are in a bad shape,'' he said.

It was reported that a police boat found the body under water after a fisherman raised the alarm.

Miss Lapthorne's father Dale, her brother Darren, and boyfriend Simon Imberger have travelled to Dubrovnik seeking clues.

They had hired a private investigator to help. An Australian Federal Police officer has also been sent to Dubrovnik.

Mr Lapthorne reportedly spoke to police only an hour before investigators found the body yesterday. Within an hour of Mr Lapthorne walking out of the police station, grim-faced forensic investigators marched out and piled into a four-wheel-drive to travel to the apparent crime scene.

Last week, police in Croatia questioned the son of the owner of the hostel where Miss Lapthorne was staying before she disappeared. Police discovered Miss Lapthorne had called Ivica Perkovic by phone on the night before she disappeared. After hours of examination he was released.

Yesterday, Mr Lapthorne revealed an anonymous caller told him that a woman tried to post Miss Lapthorne's Australian passport back to Australia on the day she was reported missing.

Mr Lapthorne said the caller suggested the woman helped run the hostel where Miss Lapthorne had been staying.

The woman left with the passport when she was told she could not send it through the post.

''The person who attempted to post the passport would have had access to Britt's passport,'' Mr Lapthorne said. AAP