Yambol regional governor Georgi Chalakov has confirmed that people died in two pile-ups on the Trakia motorway near the town. He said the number of dead is not yet known.

The first report of a multi-vehicle crash on the carriageway towards Burgas came at about 7am. A second pile-up followed soon after, this time on the carriageway towards Sofia. Dozens of cars and lorries were hit.

"The situation is very serious," Chalakov said. He and the police say people are trapped in the vehicles. Police and rescuers are clearing a route to the victims, but reaching them is hard.

Three people in a life-threatening condition have been taken to the emergency unit at the hospital in Yambol. The total number of injured is not known.

Medical helicopters cannot reach the site because of thick fog and very poor visibility, Chalakov said. A military Spartan aircraft has been sent to the crashes. It is not confirmed whether it has already carried any injured people, and its task has not been made clear.

Early reports say fog was one of the causes of the crashes.

On 9 November we reported on another crash on the Trakia motorway near Karnobat, around the 340th kilometre towards Burgas. Police say the Honda driver, a 63-year-old woman from Karnobat, died at the scene after an Audi hit her car.

The motorway is closed near the crashes. A BG-ALERT warning has gone out to the Yambol, Burgas and Sliven regions, and drivers are being diverted through Karnobat and Petolachkata.

Updated (10.11, 10:26): More than 10 people have died in two crashes, Yambol regional governor Georgi Chalakov told BTA. About 50 vehicles are involved, and 14 fire crews are at the scene. Four people with serious injuries have been taken to St Panteleimon hospital in Yambol, and eight more will be admitted to the hospital in Sliven.