Police in Australia today said they had suffered a setback in their investigation into the disappearance of Sussex tourist Peter Falconio.

The DNA profile of a man arrested in connection with the case did not match the suspect they are looking for, detectives said John Daulby, Northern Territory assistant commissioner of crime, said the profile of the man does not match the DNA found on the clothing of Mr Falconio's girlfriend, Joanne Lees.

It had been hoped the arrest could lead to a breakthrough in the police search for the suspect.

Mr Falconio and Miss Lees, who lived together in Hove, were ambushed on July 14 last year as they travelled in their camper van on the deserted Stuart Highway, north of Alice Springs.

Miss Lees told police the attacker tied her up but she managed to struggle free and escape into the bush, where she hid for six hours while he searched for her with his dog.

She said she heard a gunshot and police have been working on the theory the hijacker murdered Mr Falconio and dumped his body.

Mr Falconio's body has not been found. His disappearance sparked one of Australia's biggest manhunts.

A Press conference was being held by Northern Territory police today.