The tunnel is on the Chuo Expressway and connect Tokyo to western cities (Monkist/Creative Commons).

The Sasago Tunnel is one of Japan's longest, reaching 4.7km in length.  Located about 80km west of Tokyo, is part of the main road that connects the capital to western parts of the country.  

When emergency crews first entered, they found 110 meters of concrete panels crushing cars.  After a few hours, crews were forced to retreat in fear of a secondary collapse.

At least seven are still missing.

[video:]

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