THE parents of Nóra Quoirin believe a "criminal element" was involved in their daughter's death.
The body of the 15-year-old, whose mother Meabh is from Belfast, died after vanishing on a family holiday in Malaysia in August.
She was missing for 10 days before her body was recovered.
Speaking publicly for the first time since their daughter's death, Meabh and Sebastian Quoirin said they were determined to learn the truth.
"She could tell you the capital of every country in the world virtually ... travel enriched her world" - Meabh Quoirin remembers her daughter Nóra | https://t.co/zjWq8vjQs0 pic.twitter.com/1q6ooS1pUj
— RTÉ News (@rtenews) December 17, 2019
They told RTÉ News serious questions remained.
"For us something very complex happened. We have insisted from the beginning that we believe there was a criminal element to what happened," Mrs Quoirin said.
"And crucially we're struggling because it was difficult to get resources in place fast enough to investigate a criminal angle.
"While a post mortem when it comes through may give us answers, and has already given us some basic answers around what caused Nóra's death, it doesn't explain any of how she could possibly have got to where she was found."
Her family maintains that for Nóra to wander off would be out of character. Malaysia police, however, treated it as a missing persons case, and found no evidence of foul play.
The Quoirins said they were still waiting on results from two post mortem examinations carried out in Malaysia and London.