Police said they feared a number of people may have died when a coach went up in flames after it crashed into a truck Monday morning in southern Germany, injuring 30 people and leaving 18 others to be accounted for.
"We're afraid that people may have died in the accident," police spokeswoman Irene Brandenstein told The Associated Press.
She said several people were severely injured in the crash near Muenchberg in Bavaria.
Two drivers and 46 people and were on the bus, Brandenstein said.
German news channel n-tv showed images of the bus which was burned down to a black, smoking skeleton.
Several helicopters and ambulances were on the scene to rescue the injured and the A9 highway was closed in both directions because of the accident.
Brandenstein said the bus crashed into the truck at the end of a traffic jam. She had no information immediately about what happened to the truck driver. She said she had no information about who was on the bus and where it had come from.
According to the Bild newspaper, the coach was traveling from the eastern region of Lausitz and heading for Nuremberg.
The accident struck near the town Bayreuth, which draws thousands of classical music lovers every summer to its opera festival.
The region close to the Czech border is also dotted with spas and castles, and the A9 is a trunk motorway leading to many popular summer holiday spots.
If those missing are confirmed killed, the accident at the start of the summer holiday season would be one of the worst to hit Germany.
Among the deadliest in recent years was a collision in June 2007, when 13 people were killed as their tour bus drove off the road and plunged several metres down a slope in eastern Germany's Saxony-Anhalt state.
In September 1992, 21 people died when a bus swerved out of its lane and struck a truck before ramming into the road divider in the southern Black Forest region, a key tourist destination.
Across Europe, the last such fatal accident struck on January 21 in Italy, when an accident involving a Hungarian bus carrying teenagers left 16 dead.
In France, a head-on crash in October 2015 between a truck and a bus carrying pensioners claimed 43 lives as both vehicles burst into flames.