THE brutal murder of teenager Marioara Rostas, whose body was uncovered in a shallow grave in the Wicklow Mountains, has shaken even veteran detectives, investigators said.
A post-mortem examination - which is not yet fully complete - confirmed the 18-year-old Romanian died from a gunshot wound after vanishing from a central Dublin street just weeks after arriving in Ireland.
Chief Supt Michael O'Sullivan described it as the most heinous of crimes which shocked all the investigating officers and experienced search teams who found her partially decomposed body on Monday.
"I can say she suffered an appalling death that is incomprehensible in a civilised society," he said.
Gardai said they have made a significant advance in their inquiry into the killing four years ago which led them to the makeshift grave in remote wilderness close to the Kippure estate and the Sally Gap.
The remains were wrapped in a plastic bag.
Murder detectives said Ms Rostas was begging on Lombard Street East at the junction with Pearse Street in the capital when she got into a car, described as a silver Ford Mondeo on January 6 2008.
A car was since seized by gardai and remains in their possession.
Several possible motives are being examined and it is believed there may have been a period of time between her going missing and being murdered.
The killing has been linked to a notorious Dublin criminal and a relative of his, and it is believed she might have been sexually assaulted over a number of days before being shot dead and her body dumped.
It is thought she may have been held in a house in Brabazon Street, in The Coombe area of the south inner city, which was subsequently set on fire.
The house remains a "key location" in the inquiry and a forensic examination was carried out.
"Marioara was a harmless, defenceless young woman, 18 years of age - she looked younger than that," said Chief Super O'Sullivan.
"She was in this country for about three weeks, she was abducted... brutalised and murdered for no apparent reason."
Gardai said certain individuals who have information should come forward, in confidence, and they particularly appealed for two people who got in contact before to do so again.
After an appeal on the television series CrimeCall in April 2008, a man telephoned gardai from Co Wexford, in June that year, while a woman made contact in September with information.
Seven people were arrested - five men and two women - in November 2008 and October 2009 in connection with the murder.
They were all questioned under Offences Against the State Act.
Arrangements are now being made to bring Ms Rostas' family to Ireland before repatriating her remains.
The plastic bag containing her body was discovered in a grave a few feet deep during the latest in a series of digs on land outside Manor Kilbride, Co Wicklow.
The searches, next to Coillte-owned land and scrubland close to the Kippure estate, began on January 11 following a tip-off.
It is understood gardai received more definite information in recent days leading to the discovery.
Ms Rostas was reported missing by her parents on January 9, 2008. Her younger brother was the last person to see her alive.
Detectives do not believe Ms Rostas knew the man who picked her up in Dublin city centre.
The suspect in her death is also suspected of involvement in the gun murder of 19-year-old Darren Cogan, from Bluebell Road, Dublin, in the Blackhorse Inn in Inchicore in June last year.