Her brother, Darren, has been in Dubrovnik pushing for an intensification of the police search and her father, Dale, is expected to arrive late today.

Mr Kukrika said he understood that the family were upset but said they may have inadvertently made the "investigation harder" and that it was important for all to show "mutual respect".

"When her father comes, we will give him everything we have and everything that has been done and that which has been confirmed by the Australian policeman," he said.

"But without these six people our hands are tied."

Ms Lapthorne is known to have cooked dinner in the hostel on the night of September 17 with her friends and the group watched DVDs until about midnight before heading off to the club.

She never returned and was reported missing by the hostel owners the following day.

Both the hostel owners and their son have declared that he only spoke to the group in the hostel very briefly and that a phone call logged from Ms Lapthorne's phone was to the hostel's phone but that he had been sleeping and did not hear it.

Mr Kukrika confirmed that a "list" of mobile calls made on Ms Lapthorne's mobile on the evening of her disappearance were "of great interest" but insisted that the key to the mystery may lie with the young six backpackers.

The missing travellers are Australians David Joshua Barbalet, 21, of Perth; Jason Barry Levy, 22, of Adelaide and Lydia Evelyn Hambrook, 28, of Adelaide. There were two Portuguese travellers, Marina Moreira and Guilhermo Augusto, an American, Viktor Dabowiecki and an Englishman, Garet James Hopkins.

David Barbalet, believed to be a student at Monash University, wrote in an email reported yesterday, that he last saw the 21-year-old at the club before he left at 3.30am on September 18.

It was reported that she was very drunk and that there may have been an altercation in the club. However, the manager of the club, Vinko Cosmai, told the Herald last night that his staff would remember such an incident: "We are not used to such things happening here. I feel strongly about my country and I have always protected foreigners. Staff who work here are selected that way, they would remember and this is not the kind of place where such a thing would not be noticed."