Three people were killed and one injured in three road accidents that occurred in a 45-minute spell on the same stretch of the Thiva-Livadia national road on Thursday night.
Two men, aged 42 and 61, were killed when a truck collided with a tractor.
A crowd gathered at the spot and the third man was killed when he tried to cross the road and was hit by a passing car.
The victim was 37 years old.
A traffic police officer was also seriously injured when he was hit by a car as he was directing cars past the crash site.
Local authorities have complained about road safety in the area as many truck drivers use the road to bypass tolls on the Athens-Thessaloniki national highway.