Lisa Dorrian's body has never been found

They contacted him after his appearance on the BBC's Spotlight programme about the missing shop assistant.

It is now three months since Lisa, 25, disappeared after being at a party in a caravan at Ballyhalbert on the Ards Peninsula.

Mr Ervine said he had had two meetings recently which had "shed more light" on Lisa's disappearance.

He said he would not withhold any information he received from either Lisa's family or the police.

The PUP leader, whose party has links with the Ulster Volunteer Force, described the circumstances surrounding the murder as a cesspit, adding: "If you leave cesspits alone they multiply."

Lisa's uncle, Terry Dorrian, said they would meet with anyone who could help them find Lisa's body.

He said Mr Ervine had stressed that his involvement in trying to help the family was humanitarian and he had no political agenda.

Mr Dorrian said it was important for the wider community that his niece's body was recovered.

PUP leader David Ervine met with Dorrian family

People should "hope and pray that this is the last time a young girl's life is taken for no reason", he added.

He appealed for anyone who had any information, no matter how trivial it seemed, to make it available.

Lisa's body has never been found. Three men were questioned about the killing but were later released.

The police are looking at the possible involvement of members of the Loyalist Volunteer Force.

The UVF and the Red Hand Commando have been "investigating" the disappearance.

Earlier this month, Mr Ervine said he feared loyalists may take the law into their own hands unless the police caught Lisa's killers.

The family is offering a �10,000 reward for information leading to the recovery of Lisa's body.