One of Scotland's top lawyers, Paul McBride QC, has died in his sleep while on a business trip in Pakistan.
Mr McBride, 48, was found dead in his bed at a hotel in Lahore this morning, a spokesman for the family said.
The lawyer, who two men are accused of conspiring to murder along with Celtic manager Neil Lennon in an explosives plot, was in the country on a business trip with human rights lawyer Aamer Anwar.
A statement issued by Jack Irvine on behalf of Mr McBride's family said: "Paul died in his sleep last night in a hotel in Pakistan and at this time we would ask you to respect the privacy of his family."
Mr Irvine added: "I understand Paul was found dead in bed this morning. He had been in Pakistan for a few days and I am uncertain when he was to return to Scotland. The family have asked that they are not troubled at this distressing time."
He said there would be no further statement in the meantime.
Mr McBride was appointed a QC at the age of 35, said to be the youngest QC ever appointed in the UK.
He was called to the Scottish Bar in 1988 and has been involved in many high profile criminal cases in Scotland.
Mr McBride is one of the most highly regarded and highest-profile criminal lawyers in Scotland and was involved in the Moira Jones murder trial, the Rosepark care home fire fatal accident inquiry, as well as representing Celtic Football Club.
Mr McBride is a former member of Labour and the Scottish Conservatives. He left the Scottish Conservatives last June after Ruth Davidson was elected to lead the party north of the border.
Lawyers and politicians were quick to pay tribute to Mr McBride after hearing the news of his death.
First Minister Alex Salmond said: "This is sad and shocking news. Paul McBride was an outstanding Advocate, and a very substantial public figure in Scotland.
"Paul's genius lay not just in applying his first-class mind to the complex procedures of Scots Law, but also his unrivalled ability to explain and promote the laws of Scotland to a wider public.
"His reservoir of talent was great indeed, and I believe he had so much more to contribute to the law, and to the great debate on Scotland's future. Paul will be sorely missed across Scotland's legal system, political parties, sport and journalism."
Two men are currently on trial at the High Court in Glasgow accused of conspiring to murder Mr McBride, Mr Lennon and former MSP Trish Godman by sending improvised explosive devices to them between March 1 and April 15 last year.
Trevor Muirhead, 43, and Neil McKenzie, 42, are also accused of conspiring to murder various people in the premises of republican organisation Cairde na hEireann in Glasgow, by sending improvised explosive devices to them.
It is alleged that both accused, who deny all charges against them, believe the devices were capable of exploding.
Muirhead and McKenzie also deny an alternative charge of conspiring to cause an explosion of a nature "likely to endanger life or cause serious injury to property".
Lord Advocate Frank Mulholland and Solicitor General Lesley Thomson said in a statement: "We are very saddened by the awful news that Paul has died in his sleep overnight in Pakistan. This is devastating news for his partner Gary, family and his friends. We offer our sincere and deepest sympathies to them.
"Paul was in the prime of his life. He lived life to the full and had contributed so much to the legal profession, the media and public life in Scotland.
"He had a fabulous intellect and was interested in so many things. He was a fearless advocate who was not afraid to speak out about injustice and intolerance.
"He will be sorely missed."
Celtic chief executive Peter Lawwell issued a statement saying everyone at the football club was shocked and saddened to hear the news of Mr McBride's death in Pakistan.
He said: "This is tragic news. Paul was a very good friend of Celtic and someone who cared passionately about the club. His passing is clearly a great loss and he will be sadly missed.
"The thoughts and prayers of everyone at Celtic are with Paul´s family at this very difficult time."
Brian McConnachie QC, Vice-Chair of the Faculty of Advocates Criminal Bar Association, said everyone was "absolutely stunned" and "deeply saddened" by his death.
He said: "Paul was very young and had achieved a tremendous amount in such a short space of time and undoubtedly had a great deal more to achieve both legally and no doubt in other fields.
"From a personal point of view Paul was a very good friend to me over a number of years. In common with many people I've had a great deal of generosity from Paul, in particular his time.
"He was a very gifted lawyer and an incredibly intelligent man. I think a lot of that has perhaps been forgotten or ignored because of his high media profile in recent years in relation to politics and football.
"But he was involved in a significant amount of cases throughout his career at the bar which have had a very important impact on the development of Scots law.
"As a man he was very much a larger than life character in that if you knew Paul at all you very often heard Paul before you saw him. He always had something to say and had opinions on many subjects that he was not afraid to express."
Lord Reid, a former Celtic chairman, said: "He was a great colleague and friend and will be sadly missed well beyond his own family. My thoughts are with them. We exchanged texts only a couple of days ago."
Jackson Carlaw, Tory MSP, said: "Paul McBride was a personal friend and I am shocked at this news which all of those who knew him will find difficult to take in.
"Paul was an outstanding legal talent and a hugely colourful personality with a razor sharp mind. I enjoyed the challenge and energy he brought to conversation and debate and I was grateful to him for his personal support in recent times.
"For his parents and family this is a huge personal loss and my thoughts and sympathies are very much with them."
Johann Lamont, leader of Scottish Labour, said: "Paul McBride was one of the finest legal minds of his generation. While we didn't always agree, I always thought of him as a thoroughly decent man. When he entered the political debate he was always challenging and his intellect greatly enriched it. He will be missed."
Willie Rennie, leader of the Scottish Liberal Democrats said: "Cutting short Paul McBride's full and colourful life is so sad. Scotland will be a lesser place without him."
A spokesman for the Faculty of Advocates said Mr McBride was a valued member and colleagues were saddened at the news of his death at such an early age.
Mr Anwar told BBC Reporting Scotland how he found Mr McBride dead in his room at the Pearl Continental hotel on Sunday morning.
Both lawyers had been attending a wedding the previous evening meeting government ministers but Mr McBride returned to his room early feeling unwell, Mr Anwar said.
He said: "I tried to phone him this morning when I got up but I thought he must be asleep. I phoned him several times during the course of the morning and he didn't answer so eventually I went to his room and knocked on the door."
He said he called security to open the door after Mr McBride failed to answer.
"They broke the door open and then went in. Security came in with me and then we found Paul, he was cold, he was asleep, I thought he was asleep," Mr Anwar said.