Train search for survivors, clues
Scores die when Japan commuter train crashes into apartment building
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TOKYO, Japan (CNN) -- Japanese investigators are probing the cause of a commuter train crash that has left at least 73 people dead and hundreds more injured.
Emergency crews are searching for people trapped alive in the wreckage of the train which left the tracks and slammed into an apartment building near Osaka in western Japan on Monday morning.
Working overnight under floodlights, rescuers used cutting tools to peel away the crumpled metal entrapping several badly injured people.
They also recovered another 16 bodies, pushing the death toll up from 57 to 73.
"The first train car (is) totally crashed into the building and it looks like so flat," witness Daisuke Kashio told CNN.
Meanwhile, investigators suspect speed and driver inexperience may have been the cause of the accident but are not ruling out other explanations.
Railway officials are also checking the train's automatic braking system to see if it was operating properly.
The train's driver -- identified as Ryujiro Takami, 23 -- is still unaccounted for, The Associated Press reports.
Railway officials said the driver had been on the job less than a year, but was accompanied by a conductor, who was a 15-year veteran.
The train overran the stop line at the last station before the wreck, and the driver had been given a warning after overrunning a station in June 2004.
The railway is investigating reports that the train was running more than a minute late on the Japanese train system that normally functions like clockwork, before partially overshooting the final station before the accident.
Japan Rail West representatives said they were not sure how fast the train was going at the time it derailed, but noted it would have to be traveling at more than 83 mph (133 kph) to derail due to excess speed.
Japan's Transport Minister Kazuo Kitagawa told reporters he would order all of Japan's railway operators to conduct safety inspections in the coming days.
"It's tragic," Kitagawa said at the scene. "We have to investigate why this horrible accident happened."
The first three cars of the seven-car train operated by Japan Rail West derailed around 9:20 a.m. (8:20 p.m. EDT) on Monday.
"I was standing. The train driver hit the brakes all of a sudden, making a loud sound," said a man who was on board the train.
"The train shook violently. I tried to hold onto a hand rail, but the train shook so hard I let go, fell on the ground and my leg was hit hard. Everyone was panicking."
Passengers said the train had been late leaving the previous station.
"The train over-ran a stop at the previous station and so it backtracked," a visibly shaken man in his 20s, his face bloodied, told Japanese broadcaster NHK.
"So I guess the driver was in a hurry because the train was running late.
"The train was moving so fast, we hit a turn and I didn't think we'd make it," Reuters quoted the man as saying. "Then the train derailed."
Police said 580 people were on board at the time of the accident.
Officials said the train hit several cars, but it was uncertain whether they were struck before or after it derailed.
The accident was the worst rail disaster in nearly 42 years in Japan, where deadly train accidents are rare.
A three-train crash in November 1963 killed 161 people in Tsurumi, outside Tokyo.
In Japan's last major accident, five people were killed and 33 were injured in March 2000, when a Tokyo subway hit a derailed train.
An accident killed 42 people in April 1991 in Shigaraki, western Japan.
An earthquake in 2004 caused a bullet train to derail -- the first since the high-speed trains went into service 40 years ago.
Japan is home to one of the world's most complex and heavily traveled rail networks.
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