There will be no prosecutions following a probe into the murder of a German backpacker in Northern Ireland in 1988, it has been announced.

The body of Inga Maria Hauser was found in a remote forest in Co Antrim, 14 days after she was last seen alive on a ferry from Scotland.

The 18-year-old’s death in April 1988 remains one of the region’s most high-profile unsolved murders.

A solicitor for the Hauser family said they were distraught at being no closer to finding who was responsible, while police have vowed to continue their investigation.

A 60-year-old man and a 57-year-old woman were recently investigated by the Police Service of Northern Ireland (PSNI) over the killing.

A file was passed to the Public Prosecution Service (PPS) in 2019, who on Wednesday announced its decision not to pursue prosecutions.

In a statement the PPS said the police file was carefully considered by senior prosecutors but it was concluded that there was not a reasonable prospect of conviction for any offence.

It added that all decisions around prosecutions are taken by the application of the Test for Prosecution, as set out in the PPS Code for Prosecutors.

The PPS said there was not enough evidence to link the first suspect to the victim and that a lack of clarity around the date of Ms Hauser’s death undermined the case against the suspect.

We in the PPS acknowledge the deep disappointment felt today by the family and friends who loved Inga Maria and still miss her

Meanwhile, the PPS concluded there was insufficient evidence to establish that the second suspect had possessed and withheld information that would have been of material assistance to the police investigation.

Deputy Director of Public Prosecutions, Michael Agnew, said Ms Hauser’s sister Friederike was informed of the decision on Wednesday morning via video conference.

“The murder of Inga Maria Hauser causes enduring distress and pain over 32 years later,” he said.

“We in the PPS acknowledge the deep disappointment felt today by the family and friends who loved Inga Maria and still miss her.

“The file received by the PPS contained the product of extensive PSNI investigations and was given the most careful consideration by a team of highly-experienced prosecutors. The Test for Prosecution was applied to this evidence, in line with our Code for Prosecutors.

“The standard of proof required in a successful criminal prosecution is high. The PPS can only prosecute a case which is assessed as having a reasonable prospect of conviction. In this case, our conclusion was that the available evidence was insufficient to meet this standard and therefore the Test for Prosecution was not met.

“We have offered reassurance to the family of Inga Maria that this decision was taken only after a most careful and thorough consideration of all available evidence.”

In 2018, on the 30th anniversary of the crime, detectives said they believed a number of people may have been involved either directly in the murder or in the subsequent cover-up, and said they only need fractional pieces of evidence to bring the chief suspects to justice.

Police have a male genetic profile found at the murder scene.

A number of years ago, in one of the largest DNA screenings undertaken in the UK, 2,000 samples failed to produce a definitive match.

Ms Hauser had travelled through England and Scotland and, according to diary entries, intended to travel south to Dublin after her ferry docked at Larne, Co Antrim.

For reasons as yet unexplained, she ended up going in the opposite direction and was found dead two weeks later in a remote part of Ballypatrick Forest.

Detective Chief Superintendent Raymond Murray said the police probe would continue.

“This is difficult news for Inga Maria’s family and also for the detectives who have spent many years trying to bring those responsible before the courts. However, this decision does not signify the end of the enquiry for police,” he said.

“Unfortunately, due to the current health protection regulations, we have been unable to meet with the family as we would normally do, however I was able to discuss this investigation with Inga Maria’s sister Friederike via video conference facility hosted by the PPS earlier today and can reassure her that we remain as committed as ever to bringing Inga Maria’s murderers to justice.”

He described a “huge and complex investigation”, including a long-term forensic effort, adding that they watched developments in science in the hope they may assist the probe.

The detective also made a fresh appeal for information for anyone who could help to come forward, adding: “Do the decent thing.”

Speaking for the Hauser family, solicitor Claire McKeegan said they wanted to see the appointment of an independent panel to look at the murder, and would request an inquest.

I am profoundly disturbed by the lack of progress and in particular that substantive evidence is now no longer available

“After all of this time we are no further on in terms of identifying the person responsible for this heinous crime. The family are distraught as a consequence,” she said.

Ms McKeegan also issued a plea for anyone with information about the case to come forward.

“We intend to consult with the DoJ regarding the immediate appointment of an independent panel supported by independent researchers into this murder,” she said.

“This will require to be made up of an independent pathologist and independent lawyer and a senior independent police officer brought in from outside of this jurisdiction.

“We also intend to write to the coroner now that the police investigation has stalled to seek an inquest.”

Meanwhile, academic Professor Phil Scraton said the family needed to be assured that the initial investigation into Inga-Maria’s death was thorough and appropriate.

“Having worked on this case along with the legal team and the family, there are major causes for concern regarding the thoroughness of the initial police investigation and the subsequent time lapse,” he said.

“I am profoundly disturbed by the lack of progress and in particular that substantive evidence is now no longer available.”