The father of missing Australian woman Britt Lapthorne admits his daughter was on medication the night she went missing, which could have made her more intoxicated than she thought.
An autopsy is just getting underway on remains found on the coast near Dubrovnik but police say they are unlikely to be those of the 21-year-old, who has been missing since September 18.
Dale Lapthorne says some stories from the night just don't add up.
"I don't want to make an excuse but it may be part of the reason that Britt felt or acted very intoxicated.
"Others have said she bought very few drinks that night, so why would she be so intoxicated? It's very strange."
Earlier today human remains were found in a cove near Dubrovnik which were first thought to be the missing backpacker.
But police say they are badly decomposed and are unlikely to be those of the 21-year-old, who's been missing since September 18.
Dale Lapthorne has told 2GB's Chris Smith the news was upsetting and he was especially concerned to first hear the news from reporters, not the police.
"There was no word from police. Then we were told they couldn't determine whether the body was male or female.
"Then we were told it was in a fairly bad state of decomposition, which we found really strange."
Mr Lapthorne said he had already informed his wife that Britt's body had been found before he heard, again from media rather than police, that the body was unlikely to belong to Britt.
He has labelled Interpol "a farce" and says he will continue to put pressure on Croatian police, who he thinks have been handling the case poorly.
"We do have the homicide detective back from Zagreb and he's a bit of a goer but I'm just concerned that underneath that there's nothing."
"...I've obviously rattled their cage a lot and I'll continue to rattle their cage when they don't perform. I've got nothing to lose and if they're not doing anything, what's the difference?"