91�ȱ�

The Crown Office has identified new lines of inquiry into the death of a Fife man who died from a stab wound to the chest.

Colin Marr died from a single blow from a kitchen knife in 2007 after a row with his fiancée Candice Bonar.

The 23-year-old's family has gathered new material about the case, challenging the original police conclusion that it was suicide.

Ms Bonar has always maintained her innocence.

Colin's stepdad Stuart Graham handed over a cache of material to Police Scotland, which the family say should be investigated further.

It includes the findings of a report by leading pathologist Dr Nat Cary.

Dr Cary said it was "both possible and plausible" that Colin's injury was "inflicted by a third party", and questioned previous police reports on the location of the stab wound.

The material was passed to the Crown Office by the police.

In a letter to Scottish Liberal Democrat leader Willie Rennie, who has helped the family for nearly a decade, Lord Advocate James Wolffe, said: "Prosecutors have considered the material and have identified further lines of inquiry that they will pursue."

Mr Graham told 91�ȱ� Scotland the family "welcomes any further inquiries into the significant evidence shared".

He said: "A priority for us is that they quickly establish the actual wound location as outlined by Dr Cary, and the significant implications to the previous findings from fingerprint experts.

"There were other significant statements we have shared with Police Scotland regarding who went to the house and when, but no one has asked for the contact information."

Both Fife Police and the Crown Office previously produced reports that were critical of the original investigation into Colin's death and issued apologies to his family.

The Police Investigations and Review Commissioner also upheld 12 complaints over the force's handling of the case.

'Heart-breaking nightmare'

Earlier this year both Police Scotland the Crown Office said they would consider any new material relevant to Colin's death.

Colin's fiancée Ms Bonar has been interviewed three times by the police and voluntarily appeared in person at the 2011 Fatal Accident Inquiry (FAI) into his death.

At the inquiry Sheriff Alastair Dunlop said he could not decide if the death was suicide or homicide

Speaking after the FAI, Ms Bonar said: "My name is cleared. I have always been honest and declared my innocence throughout this heart-breaking nightmare.

"What Colin did, he did to himself and that's the truth."