Image copyright PSNI/PA Image caption Inga Maria Hauser went missing after she arrived in Larne on 6 April 1988

A detective investigating the murder of a German backpacker in Northern Ireland 30 years ago has said that police have a suspect in mind.

Inga Maria Hauser, 18, went missing after she arrived in Larne on a ferry from Scotland on 6 April 1988.

Her body was found two weeks later in a remote part of Ballypatrick Forest, near Ballycastle, County Antrim.

Image copyright Pacemaker Image caption Inga Maria Hauser was found dead in Ballypatrick Forest 30 years ago

The teenager's neck was broken after she suffered what police called a "vicious and ruthless" assault.

'Suspected cover up'

No one has been convicted in connection with her murder.

Det Ch Supt Raymond Murray made a direct appeal to an individual he believes may have been involved in helping to cover up the killing, to come forward.

Media playback is unsupported on your device Media caption Det Ch Supt Raymond Murray appealed for people with information to come forward

"I think there are people out in the community who know exactly what happened," he said.

"I think there are one or two people who were possibly involved in the aftermath of this killing, I think there's at least one of them who's finding this difficult to live with.

"I'm asking that person today - I'm asking them very, very specifically - I'm saying you need to go away and have a think.

"We're all getting older, we're all moving on - is this something you want to take with you to the grave?

Image caption A photo of Inga Maria used in a previous PSNI appeal

"Some people struggle and I think this person is struggling. It is not too late now to examine your conscience and come forward to the police."

Det Ch Supt Murray said the Police Service of Northern Ireland (PSNI) is "still very close to solving" the case.

"We have a good strong hypothesis about what happened and all our investigations have not weakened that hypothesis, they have gradually strengthened it," he said.

"We have a suspect in mind," he said.

Image caption A memorial to Miss Hauser near the spot where her body was discovered

DNA at scene

"We're investigators and we keep an open mind, but the evidence and information and intelligence that we have to date had led us to focus on a very, very small number of individuals.

"I cannot rule out the possibility that more than one person was involved in Inga Maria's death.

"I also have a report that a man in the rural area east of Ballymoney was seen soon after the murder in April 1988 with scratches on his face and that there was concern in the community that he had some sort of involvement."

The officer confirmed those suspected individuals are still alive, but would not confirm if they are still living in the north Antrim area.

He added that identifying DNA belonging to an unknown male that was found at the scene was key in the investigation.

Image copyright PSNI Image caption The PSNI have issued a new appeal on the 30th anniversary

"We have made huge strivings in trying to match that DNA, we've talked face-to-face with around 1,700 people," Det Ch Supt Murray said.

"We have used cutting-edge science to try to match that DNA but that DNA has not been matched to date and we believe that is a very significant line of inquiry for us.

"There may well be somebody out in the community who knows who that DNA belongs to.

"We're waiting for the results of further familial DNA testing that covers the entire United Kingdom - literally we're expecting those to be delivered within the next few days."

The officer said diary entries showed Ms Hauser had been excited to travel to Northern Ireland.

A postcard to her friend in Germany read: "My journey through England is wonderful - I'd rather not come back. The day after tomorrow it's on to Ireland, which pleases me most of all."

Her last notebook entry, dated 6 April on the day she went missing, read: "'Went from Glasgow to Ayr and from there to Stranraer to get over to Ireland. Saw the sea. Beautiful and mysterious. Wonder where I stay tonight. Need more money."

Image caption A police cordon was set up after Ms Hauser's body was found in 1988

Det Chief Supt Murray appealed for anyone who saw Ms Hauser at Larne ferry terminal to come forward.

He said she had planned to make her way to the railway platform and travel south from Belfast to Dublin, but had ended up travelling in the opposite direction.

He said: "We know she was on the boat but we've never had a confirmed sighting of her either getting into a vehicle on the ferry or coming off the ferry.

"That information to us would be extremely significant."

'Family suffering'

Det Chief Supt Murray said he had recently travelled to Munich to meet Ms Hauser's sister.

Her father Josef is dead, and her mother Almut is extremely ill.

Image caption The victim's parents were filmed during a previous appeal in 1989

The officer said: "Inga Maria's sister shows clear signs of stress to this day about what happened all those years ago. It clearly has had a massive impact on her life .

"But we believe what happened may have had an impact on the killer or killers of Inga Maria Hauser - we think the lives of their families have suffered as well.

"We think that the lives of their families continue to suffer until this very day."

On Friday, police will travel to Scotland to appeal for people who may have seen Inga Maria Hauser there, or had contact with her, before she embarked on the Stranraer to Larne ferry.