Investigators in Austria have found their first clue to the cause of the Alpine tunnel fire which killed at least 160 skiers last Saturday.
An oil-like residue was found on the track outside the tunnel yesterday. Investigators suspect it came from the ill-fated train before it began its journey up the Kitzsteinhorn mountain at the ski resort of Kaprun.
The find was made as police published the first photographs of the burnt-out tunnel, and as rescue teams removed 128 bodies for identification.
"The material looks as though it may have dropped from the vehicle," said a technical investigator, Mr Christian Tisch. This suggests that the train caught fire before entering the tunnel.
Survivors have told of seeing smoke before the train left the station.
The material was sent for chemical analysis, and police expect results in less than two days.
It is the first substantial clue towards helping puzzled investigators work out how the engineless train, pulled by a cable, caught fire in the first place. Most of the mechanical evidence melted with the train.
But despite this clue the cause of the fire was still uncertain last night, according to investigators.
The state prosecutor's office in Salzburg is now investigating the possibility of criminal charges.
Yesterday survivors from a German ski club said they heard two strong explosions while they were in the tunnel. They managed to climb out of the carriage and had begun running down the tunnel when, they say, they heard two explosions and saw sparks shooting past them.
"Everyone in the group was in a panic, afraid that the burning train would dislodge and crash down the tunnel," they said in a statement.
As police worked inch by inch through the tunnel for further clues, rescue workers continued their physically and psychologically exhausting work recovering bodies from deep within the burnt-out area.
Over 128 bodies had been removed from the tunnel yesterday evening by rescuers working round the clock in 90-minute shifts. Work has been slowed by strong winds which have prevented helicopters from landing on the mountain. Rescuers say they expect to finish tomorrow.
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