Gardaí say they believe a Roma teenager missing for nearly a year has been shot dead.
18-year-old Mariora Rostas arrived in Ireland from Romania last year with her family and is believed to have been killed at a house in Dublin.
The house was subsequently burned out but has since been forensically examined.
Four people have been arrested in connection with the investigation but gardaí are appealing for people who contacted them anonymously with information to contact them again.
No body has yet been found but detectives at Pearse Street in Dublin are now investigating what could be a murder that has so far been covered up.
Mariora Rostas, who has been missing for nearly a year, lived at a derelict house in Donabate with no sanitation or heating.
Her 15-year-old brother was last to see her getting into a car on 6 January. The next day she made a call home to Romania and two days later her family reported her missing.
Gardaí think she was subsequently shot at a house in Dublin before her body was removed and concealed. The house was rented by the HSE at the time but has since been burned out in what gardaí believe was an attempt to destroy evidence.
However the premises has now been forensically examined and samples have been taken to find DNA or other evidential material.
On 2 June, gardaí at Pearse Street received information from an anonymous caller, three months later a second call was received.
Gardaí will this week search the Grand Canal as they try to find Ms Rostas' body and the gun that killed her. She had only been in Ireland a short while before she disappeared.
Detectives believe Ms Rostas somehow got involved with a south city criminal gang and may have been killed after they failed to inveigle her into criminal activity or the sex industry.
Four people have been arrested so far as part of the investigation, including the main suspect, a 29-year-old gang-linked criminal.
Three of the four have now been released but gardaí are applying to the Dublin District Court to extend the detention period for one of the men for another 24 hours.
