Burgas hospital has sent three ambulances with medical teams to two pile-ups on the Trakia motorway near Yambol, the hospital told BTA. Prof Asen Baltov and a team of orthopaedic surgeons left in one of them.

The motorway is closed. Four people with serious injuries have been admitted to St Panteleimon hospital in Yambol.

Both crashes happened in heavy fog. The first was at the 289km mark on the Burgas-bound carriageway. The second was at 294km, before the Zimnitsa junction, on the Sofia-bound side. Early reports say about 50 vehicles were involved in the crashes near Zimnitsa.

The hospital says the ambulances and doctors were on standby from the moment the crashes happened. They left right after regional health authorities asked for help.