THE detective leading the investigation into Sian O'Callaghan's murder has said the family were "bearing up".

Detective Superintendent Steve Fulcher was speaking outside Oxford Coroner's Court after an inquest into the 22-year-old's death was opened and adjourned earlier this afternoon.

"It is a horrific trauma for them," said Det Supt Fulcher.

"I want them to have closure and they need to organise her funeral.

"That can't happen until the defence have decided whether or not they want to have a second examination."

Coroner Nicholas Gardiner, sitting at Oxford Coroner's Court, said examinations were ongoing to determine exactly how the young woman died.

"I think the actual cause of death has not yet been defined but is likely to be head injuries of some description."

Sian was formally identified by Pete Shawe, the partner of her mother Elaine, who had known her for four years.

Speaking at the 10-minute hearing, Det Supt Fulcher confirmed Sian's death was formally certified last Thursday, following the arrest of taxi driver Christopher Halliwell, who has subsequently appeared in court charged with her murder.

Her family were not present for the brief hearing, which was held in order to expedite her funeral arrangements.

However, she cannot be buried until Halliwell's defence team have decided whether to request a second post-mortem examination, as is their right.

There is unlikely to be a full inquest into Sian's death, instead, the hearing is expected to be resumed and adjourned once criminal proceedings have concluded.

Hundreds of people are expected to turn out at a walk in Sian's memory tonight, which is to be led by boxer Joe Egan.

The event starts at 8pm from Suju, in Old Town's High Street.