Police investigating the disappearance of Sussex backpacker Peter Falconio in Australia vowed today they will not stop until his killer is behind bars.

Northern Territory Police Assistant Commissioner John Daulby made the pledge at a Press conference held to reveal the results of a review of the investigation.

He also said all the evidence corroborated Mr Falconio's girlfriend Joanne Lees' story that a gunman ambushed them on a deserted highway on July 14 last year. Police believe 28-year-old Mr Falconio was killed.

He said: "Not only does the evidence we have at the crime scene support her statement but so too do the witness accounts of those that drove past the incident as it occurred."

Miss Lees, 27, who worked at Thomas Cook in Hove, said the man flagged down their camper van as they were travelling north of Alice Springs.

He attacked the couple, who lived together in Hove, and attempted to abduct them. Miss Lees was tied up but she managed to escape and hide in the bush.

Brighton University graduate Mr Falconio has not been seen since the attack although a blood trail was found by the roadside.

Mr Daulby produced a time-line showing how the witness accounts of six people who saw the gunman's truck and the couple's van at or near the crime scene, and at one point together, fitted in with Miss Lees' story.

The 32-page review, by Northern Territory Superintendent George Owen and retired south Australian Assistant Commissioner Jim Litster, showed the investigating officers were on the right track to solving what has become one of Australia's biggest murder investigations.

Mr Owen and Mr Litster sifted through almost 23,000 pieces of information and interviewed police, witnesses and forensic specialists.

Following the review, officers are looking for the driver of a van, similar to that described by Miss Lees, who allegedly followed three British tourists on June 29 along the Flinders Highway in Queensland.

The review praised the police response to the case but said the police information system initially failed to cope with the huge influx of information on the case.

The report refuted any scepticism surrounding Miss Lees' version of events, stating that it was reasonable to expect some inaccuracies in her story since she had undergone trauma.

Mr Daulby said: "Our investigation is heading in the right direction and we will not close this case until Peter Falconio's killer is behind bars."