The serious crash on the Trakia motorway is not the first multi-vehicle pile-up with many casualties on Bulgarian roads.
In February 2019, one person died and 13 were injured in a pile-up on the Struma motorway near the village of Damyanitsa.
In July 2017, 40 vehicles collided near Ihtiman. Smoke from a burning rubbish dump and fog caused the crash. Dozens of people were injured, but no one died.
In late March 2014, another pile-up happened on the Trakia motorway, near the village of Trilistnik. Two people died and 15 were injured.