Police in Germany have confirmed that 18 people were killed when a tour bus burst into flames after colliding with a lorry in the southern state of Bavaria.

The crash happened on a motorway near the town of Stammbach on Monday.

"It's clear now that all 18 of the missing people on the bus died in the accident," police said in a statement on Twitter.

The bus had been carrying 48 people, of whom 30 were taken to hospital, some with serious injuries.

Alexander Dobrindt, Germany's minister of transport, said that 11 bodies had been retrieved from the crash site so far, and a search for the remains of the seven other victims was under way.

The blaze was so powerful "that only steel parts are still recognisable on the bus, and from that you can understand what it means for the people on this bus", he said.

'Great dismay'

German Chancellor Angela Merkel voiced "great dismay" over the crash, her office said.

"Our thoughts go to the victims and their family members, as well as to the injured. We hope that those who have been rescued will recover from their injuries," Merkel's spokesman Steffen Seibert said.

Some 200 emergency workers were deployed to the site, including firefighters, rescue workers and police, while south-bound traffic on the motorway remained blocked.

According to the Bild newspaper, the coach was travelling from the eastern region of Lausitz and heading for Nuremberg.

Police said that the 48 people on the bus were aged between 41 and 81 and were mainly from the eastern state of Saxony.

The accident is 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.