A 25-year-old Scottish woman who lay injured in her crashed car for three days because police failed to respond to an accident report died on Sunday.

Lamara Bell's family says she died in a Glasgow hospital on Sunday, a week after the accident.

She was found last Wednesday beside her dead boyfriend John Yuill, 28, in a car that had slid down an embankment near the city of Stirling in central Scotland.

Bell's brother Martin posted emotional Facebook updates on his sister's condition, the last of which read, "My sister has passed away."

"The front of her brain is basically shutting down. She is fighting it until the end," Martin wrote after doctors told him fluid buildup and swelling in his sister's brain would lead to her condition worsening.

'Huge error by a senior officer'

Police say the accident was reported, but officers were not sent to the scene until a second call three days later. Police Scotland Chief Constable Stephen House has apologized, saying police "failed both families."

"You can start down at her pinky toe and work your way up to her head and you will find a cut, bruise, graze or broken bone on every part of her body," Martin Bell wrote on Saturday. "She has been giving it her all for a week now and the first three days she had no medical care what so ever it was a miracle she was still alive when she was found on Wednesday."

Scottish politicians are calling for an inquiry into how the mistake happened and whether it is connected to police reorganization and budget cuts.

"A huge error by a senior officer has absolutely devastated us ... it feels like we have had our hearts ripped out any time I see her my heart sinks to the bottom of my stomach and it's not getting easier," Martin Bell said in his public Facebook posts.