Cold case detectives probing the brutal murder of a Scottish nurse at a religious college in the US 33 years ago have identified a suspect.
Elizabeth Mackintosh, 50, was found strangled with a cord and stabbed in the neck in the toilets of a chapel at the Covenant Theological Seminary in Creve Coeur, Missouri, in March 1990.
Miss Mackintosh, the daughter of a former Moderator of the Free Church of Scotland, was originally from Edinburgh and was studying at the seminary for a degree in counselling.
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Police launched a major murder probe at the time of her death but no one has ever been brought to justice for the killing and the case remains unsolved.
The Creve Coeur Police Department have now said they are hopeful of bringing charges against Michael Johnson, who was also a student at the seminary at the time.
Johnson, now 67, was Miss Mackintosh's supervisor for her cleaning duties at the college and the pair had an argument in the days before the killing.
He was questioned at the time of the original investigation but has never been charged.
The fresh investigation was filmed for American true crime documentary Cold Justice and showed detectives reviewing correspondence between Johnson and Miss Mackintosh days before the murder.
In a memo he chastised her for not following the chain of command about the cleaning supplies. In her response, she stood up for herself and corrected spelling errors in his memo.
In the documentary, Johnson was confronted by investigators as he left his job at a home improvement store in Tomball, Texas.
He refused to discuss the case in detail but admitted he had gone to the chapel on the day of the murder to speak to Miss Mackintosh.
He said: "I've dealt with police before and any time I've talked to police it has not gone well.
"I know that anything I say can, and it was, used against me.
"I just walked through the hall. I mean I walked by the bathroom but I didn't go in the bathroom.
"I went to talk to her about the whole issue with the bathroom. I think we have talked too much."
Miss Mackintosh worked as a cleaner at the college to earn money while studying and was attacked while cleaning the men's toilets in the chapel.
She was beaten, strangled, and stabbed in the neck. There was no sign of sexual assault.
Miss Mackintosh was the daughter of former Free Church Moderator Rev Professor James Mackintosh and his wife Hughie. Her parents both died within six years of the murder.
Her sister Helen Miller thanked the cold case investigators for their efforts and said she is hopeful of a resolution.
She said: "She was a very loving sister to me, she was very bright and creative.
"It was an unnatural, horrible death and it caused the people who loved her a great deal of pain.
"It's incredibly unfair. She was a wonderful, wonderful person and we miss her terribly.
"We have thought about this for so many years and wondered for so many years and it's just remarkable that they are able to bring something together.
"It just shows how passionate they were. Perhaps they can bring it to a conclusion now, I'm so very hopeful they can do that finally."
The documentary showed that the investigators considered three other potential suspects for the murder but ruled them out before focusing their attention on Johnson.
Creve Coeur Police Department Sergeant Douglas Manninger said: "We worked very diligently, we talked to a lot of different witnesses and we feel we have a good case."
A spokesman for the police department said their findings on Johnson had been presented to the St Louis Prosecuting Attorney's Office and they are awaiting a decision on whether he will be charged.
The case is the only unsolved murder in the history of the city, which is around 14 miles from St Louis.
More than 300 students at the college campus were questioned as part of the original investigation.
A psychological profile prepared by the FBI suggested Miss Mackintosh was the victim of a young male loner with low self-esteem.
Miss Mackintosh was a trained nurse and health visitor who had worked in Edinburgh, London, and South America. She was only a few months away from graduating when she was murdered.
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