It happened on the A1 near Dunbar.
Nation Remembers Tunisia Victims
Scottish victims of the Tunisian massacre have been remembered in a nationwide minute's silence.
The remains of Jim and Ann McQuire, from Cumbernauld, North Lanarkshire, and Billy and Lisa Graham, from Bankfoot, near Perth, arrived back in the UK yesterday.
They were among 38 people killed by gunman Seifeddine Rezgui when he opened fire on holidaymakers on a beach in the resort of Sousse last Friday.
Today, the Queen and the Duke of Edinburgh observed the silence while on a visit to Strathclyde University.
At midday, they paused along with students and university principal Professor Sir Jim McDonald.
A church service was held in Cumbernauld in memory of the McQuires while there was a candlelit vigil in Perthshire for the Grahams.
Both North Lanarkshire Council and Perth and Kinross Council are flying flags at half-mast and books of condolence have been opened.
Passengers at the normally bustling check-in area of Glasgow Airport fell silent, most standing with heads bowed, to observe the minute's silence.
Flags are also being flown at half-mast at the Scottish Parliament in Edinburgh.
The silence was also observed at the Appeal Court in Edinburgh where a hearing was taking place to decide whether relatives of Lockerbie bombing victims could pursue a posthumous appeal on behalf of Abdelbaset al-Megrahi, the only man convicted of the atrocity.
The 26 year old was first targeted in Briarscroft Road.
Euan Johnston was shot in his car last month.
The family of three crash victims took their case for the 59-year-old to be put on trial to the Appeal Court in Edinburgh earlier this year.
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