The Irish government has expressed concern after the trial of a Dublin teenager held in prison without trial Egypt was adjourned for the 14th time.
Ibrahim Halawa could face a death penalty with nearly 500 others over anti-government protests in 2013.
In April, the BBC revealed the Egyptian government had rejected allegations by the United Nations about his treatment.
His family said they had been told a number of time that a court would pass judgement on his case on Wednesday.
Mr Halawa, the son of Ireland's most senior Muslim cleric, has been held for more than two-and-a-half years since his arrest in Cairo.
In a statement, his family said they were told on Wednesday that judges now plan to reopen the case and to reassess video evidence.
It has been adjourned until 2 October.
"This decision comes as a surprise to our family, and the Irish government, in circumstances where we all understood the proceedings would come to a conclusion today," they said.
"To say we are devastated by today's outcome is an understatement."
The Irish government was represented at the court hearing and has expressed "deep disappointment and concern" at the latest development.
In a statement, Foreign Affairs Minister Charlie Flanagan said he shared the Halawa family's sense of frustration.
"I will be conveying my concerns about this delay directly to the Egyptian government," he said.
"I will be seeking more information of the review of technical evidence ordered by the court and its likely impact on this trial.
"Yesterday I met Ibrahim's father and sister and reassured them of my own and the government's continued commitment to achieving our two objectives: to secure Ibrahim's return to Ireland as soon as possible and to ensure his welfare during his detention."
Mr Flanagan added that the case is one of his "key" priorities.
The minister revealed that he met the Egyptian foreign affairs minister in Cairo on 16 June to underline the Irish government's concerns about the case.
Lawyers for the family said they plan to re-apply for Mr Halawa to be released under the presidential decree, which would mean he would be deported back to the Republic of Ireland.
Solicitor Darragh Mackin said he will meet with the Irish Department of Foreign Affairs in the coming days "to consult on the proposed way forward."
Mr Halawa was 17 at the time of his arrest after Egyptian security forces ended a siege at the Al-Fath mosque in August 2013.
Three of his sisters were also arrested, but were later released on bail.
The family said they were on holiday at the time and had sought refuge in the mosque to escape the violence outside.
They have denied claims that Mr Halawa is a member of the Muslim Brotherhood, Egypt's oldest and largest Islamist organisation.
The Eyptian government has declared it a terrorist group, a claim it rejects.
Mr Halawa and 492 others have been charged with murder and a range of other serious offences.