Fifteen people were killed and 31 injured when a passenger bus with Romanian licence plates fell into a deep river gorge in central Montenegro on Sunday, officials said.
Police said the bus had swerved off the Zdrijelo Bridge and plunged onto a rocky outcrop in the gorge of the Moraca River, about 50 km (30 miles) north of the capital Podgorica.
"This is a major tragedy for us. Fifteen people out of 46 passengers died in a bus accident. Medical crews are fighting for the lives of others," the Romanian ambassador to Montenegro, Mihail Florovici, told Vijesti TV.
He did not say whether the dead were Romanian. Montenegro's interior ministry earlier said 13 people died.
A Reuters photographer on the scene said the wreckage of the bus was lying on its side on an outcrop about 30 metres (90 feet) down in the gorge, where police and rescuers were seen trying to retrieve dead and injured passengers.
Police cordoned off the area and the main road linking Podgorica with the north of the country.
Although the small Balkan country has invested tens of millions of euros in infrastructure over the past decade, traffic accidents are frequent, especially in summer when tourists flock to its Adriatic coast.
Health authorities said eight of the injured were in intensive care in a Podgorica hospital.