ARLENE Arkinson disappeared on August 14, 1994 in Co. Tyrone, Northern Ireland.
At the time of her disappearance, the Northern Irish schoolgirl was 15 years old.
She was last seen in a car with Robert Lesarian Howard, a man who would later be sentenced for life imprisonment for the murder of a teenage girl in England.
Here's what we know about the disappearance of Arlene Arkinson in 1994 and the last man who saw her alive.
Who was she?
Arlene Arkinson was born on Aril 4, 1979.
Her mother died when she was 11 years old.
She lived with her father and seven older siblings in Spamount, a townsland near the Donegal border in the northern part of Co. Tyrone.
Ms Arkinson had been sexually abused by her brother-in-law Seamus McGale, who was convicted and jailed in 1993. He was released 10 days before she went missing.
She was 5ft 4in, medium build, white, described as having a "fresh" complexion, with blue eyes and fair hair.
What happened to her?
It was not unusual for Ms Arkinson and her friends to go to discos across the border in the Republic.
The friends would at times get a lift to the discos with Robert Lesarian Howard.
Who is Robert Lesarian Howard?
Robert Lesarian Howard was the last person to see Ms Arkinson alive.
Born in 1944 in Co. Laois, Howard had moved several times between Ireland and Britain.
He tortured and sexually abused Ms Gahan before she threw herself from a window in the flat and ran to the police station.
He was out on bail at the time of Ms Arkison's disappearance.
In the small hours of the morning, Arlene Arkinson was seen alone, driving away with Howard in his car down a country road.
Howard was arrested on suspicion of kidnap and murder and questioned some 13 times over the course of two days, but was not charged at the time.
What happened to Howard?
In 2003 Robert Lesarian Howard was found guilty of the murder of south London teenager Hannah Williams.
In 2001 the 14-year-old went missing during a shopping trip.
Howard was already known to Ms Williams through her father's ex-partner, who shared a house with Howard in Deptford.
In 2002, almost a year later, her body is found in a disused cement factory in Kent.
His conviction could not be reported in 2003 because he was still facing separate sexual offence charges in Northern Ireland.
He is jailed in HMP Frankland Co. Durham.
In June 2005, Howard was tried and found not guilty of Arlene Arkinson's murder at Belfast Crown Court.
The prosecution accused him of trying to conceal his movements the night Ms Arkinson went missing and getting other people to lie for him.
The jury did not know at that time Howard was already serving life in England for the murder of Hannah Williams.
In September of that same year, the reporting restrictions surrounding Howard were lifted.
It emerged he had a criminal record dating back 40 years.
He is known to have attempted to rape a six-year-old child in 1965 when he was 21, a young woman in 1969, and an older woman in 1973.
Robert Howard died October 2, 2015.
What about Arlene Arkinson?
An inquest was opened into Arlene Arkinson's death in February 2016, and ended in June 2016 for summer recess.
The inquest recommenced in September 2016.
During the inquest, the court in Belfast was told how Howard would have been "extremely dangerous" to Ms Arkinson given his previous history.
The court also heard that Howard's flat was always busy with "the young ones" on a Saturday and he was like "the pied piper."
They also heard how, after Ms Arkinson's disappearance, Howard hoped she was "cold and hungry".
He also asked the daughter of his partner at the time, Donna Quinn, not to tell police Ms Arkinson was with them that night as he was "out on bail or something".
Also at her inquest in Belfast Coroner's Court, the court heard that Howard had had conversations in prison in England where he allegedly admits to killing Arlene Arkinson.
"On my first, I know I got away with it," he said.
The court heard disturbing excerpts from conversations Howard had in prison between 2009 and 2012 from an unknown source.
He was quoted as saying, "See, I couldn't hold her [...] I got her over to the sink that's just inside."
"She's strong [...]I bound her," he added.
At the time, Detective Chief Superintendent from the PSNI Raymond Murray said: "This was an implicit admission at the very least, if not an explicit one, that he had got away with murder."
Note: This piece was edited for clarity. The original copy stated the inquest ended in June 2016, when the author meant it ended for summer recess in June 2016.