A woman, who lay in a crashed car off the M9 near Stirling for three days before police found her, has died.
Lamara Bell, 25, was critically injured in the crash on Sunday, but she and her partner John Yuill, 28, were only discovered by officers on Wednesday.
Mr Yuill had already died. Ms Bell had been in a medically-induced coma.
It later emerged that police had received a call about the crash on Sunday, but the information had not been entered into police systems.
Ms Bell, who was a mother, was being treated at the Queen Elizabeth University Hospital in Glasgow having suffered kidney damage from dehydration from lying in the wreckage for so long. She died at about 06:50 on Sunday.
Her brother Martin Bell confirmed her death on Facebook.
“My sister just passed away,” he said.
A statement on behalf of the Bell family said: “Sadly, our daughter has passed away. We now request that the media respect our privacy to grieve for Lamara at this very difficult time.”
A statement on behalf of the Yuill family said: “The family of John Yuill would like to say that their prayers and thoughts are with Lamara and her family.
“We are devastated by the sad news this morning.
“The families have messaged each other this morning and our thoughts are with John and Lamara’s children at this very sad time.”
The Police Investigations and Review Commissioner (Pirc) is reviewing the handling of the incident, focusing on the call on Sunday.
Chief Constable Sir Stephen House said: “On behalf of Police Scotland, we are all deeply saddened by the news of Lamara Bell’s death this morning and I would personally like to express my deepest sympathies to her family and friends for their loss.
“We will continue to co-operate fully with the Police Investigations and Review Commissioner as they undertake their investigation into the circumstances of this tragic incident.”
Last week Sir Stephen apologised to the couple’s families for the “individual failure in our service”.
On Saturday, Mr Bell put a post on Facebook which said: “I just want everyone to know Iv put my posts public .. I want the police to see this also ..I want them to see how a huge error by a senior officer has absolutely devastated us.”
He said the family felt like they had had their “hearts ripped out.”
The couple, believed to be from the Falkirk area, had been reported missing to police after last being seen in the company of friends in the Loch Earn area of Stirlingshire in a blue Clio in the early hours of Sunday.
Ms Bell’s family had said they were angry and disgusted by the way Police Scotland had handled the case.
The chief constable said a member of the public had called the 101 non-emergency number at about 11:30 on Sunday after seeing the car down the embankment near the Bannockburn slip road.
The call had been taken by an “experienced officer”, who has since remained on duty. However, “for reasons yet to be established” this was never entered into systems or sent out to operational teams in the area.
“That we failed both families involved is without doubt,” the chief constable said.
Scottish Lib Dem leader Willie Rennie said: “Her [Lamara’s] father’s bedside singing and her family’s publicly expressed anguish were clear manifestations of the love they felt for Lamara.
“We all feel terribly sad that her life has ended and in this awful way. Whilst her family and friends grieve for Lamara it is now our duty to find the answers that everyone is seeking.”
Last week Mr Rennie called for a wider inquiry into the operation of Scotland’s single police force in light of the incident.
He told BBC Scotland he had been contacted by a number of people in the police service in recent weeks alleging inadequate backfilling and a number of other issues that were badly affecting the service officers could give to the public.
Mr Rennie said a thorough investigation must be carried out into the case.
However, he said that, as well as finding answers for their families, the case should be widened out to look at staffing issues and the target-driven approach within Police Scotland.
Last week, Mr Rennie said workload pressure on the police service had been “immense” since the reorganisation of the service into a single force more than two years ago – a move which included the centralisation of police control rooms.
Scottish Labour’s justice spokeswoman Elaine Murray said: “This is awful news, and our thoughts and prayers are with Lamara Bell’s family. Losing a loved one is always difficult, but to do so in such circumstances makes the pain so much more pronounced.
“Lamara Bell’s death reinforces the need for an urgent full and wide-ranging inquiry by the Police Investigations and Review Commissioner.
“We need to get to the bottom of why it took police more than 72 hours to respond to an emergency call. This inquiry must look not just at what went wrong in this specific case, but also assess wider issues like the impact of cuts to services on the ability of the police do their job properly.”
Scottish Conservative justice spokesman Margaret Mitchell said: “This has been a devastating tragedy, and you can only feel for the families involved.
“The second death in relation to this incident really increases the pressure on Police Scotland and the Scottish government.
“They both assured the public the 101 number was working well and there was nothing to worry about, despite police officers telling a different story.
“This tragic incident proves that not to be the case.”