The death toll from Switzerland's worst road tunnel accident in several years has risen from six to nine.

Police in canton Graubünden said one of the two cars incinerated in Saturday's crash involving a bus had been carrying four, not two passengers as had been previously thought.

Another person, who was seriously injured in the accident, also died in hospital on Monday.

The collision in the 750-metre-long Viamala tunnel between a car and a bus carrying a local ice hockey team was the worst incident of its kind since 2001 when 11 people died after two trucks crashed in the north-south Gotthard tunnel.

The Viamala tunnel, which leads up to the San Bernardino, is part of a major transalpine route in southeastern Switzerland.

Police are still to release the identity of the victims. They said investigations were also continuing into the cause of the crash.

Witnesses said the car with German licence plates caused the accident. They said the vehicle lost control after one of its wheels came off. It crashed into the bus, setting it on fire.

Another car subsequently collided with the vehicles and also caught fire.

The athletes on the bus were able to flee to safety, but a team masseuse and another person from the staff are believed to be among the eight dead.

At least six people were also injured in the accident.

Safety requirements

The authorities said the nearly 40-year-old tunnel, which will remain closed at least until next Friday, meets the safety requirements.

However, there are no emergency exits, which any new tunnel of its length must have.

The government introduced a series of safety measures following the Gotthard tunnel fire in central Switzerland nearly five years ago.

They include the installation of fire alarms, radio reception inside the tunnel and improved lighting.

swissinfo with agencies

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