Scottish police are investigating how they missed responding to a car accident that left one person dead and another severely injured on the side of the road for as many as three days.

John Yuill, 28, and Lamara Bell, 25, were found on Wednesday morning local time off the M9 highway near the city of Stirling. Police reportedly received a call early Sunday about a car on the side of the road but did not follow up.

The BBC says that Yuill was dead and Bell was seriously injured when they were found by police. Family members told the BBC that Bell had broken bones and had kidney damage due to dehydration. They had been reported as missing after having had last been seen with friends early Sunday.

The BBC adds:

"The Police Investigations and Review Commissioner is to investigate, focusing on the call made to police on Sunday. A separate police investigation into the crash itself is ongoing.

"Scottish Justice Secretary Michael Matheson, who is also a local MSP for Falkirk, said he wanted 'early answers' about the tragedy, and said Police Scotland had assured him that all relevant information would be passed on to investigators

"Mid Scotland and Fife MSP Murdo Fraser said it was vital the 'truly shocking incident' was investigated in depth.

"He said: 'People lying unattended at the side of the road for days is something you'd be surprised to encounter in the third world.' "

The Telegraph reported that some politicians wondered whether a larger investigation is needed, to see if the incident was connected to a more widespread problem within Police Scotland.

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