Tunnel Collapses Outside Tokyo Kills Nine – NYTimes.com

NY Times: Tunnel Collapses Outside Tokyo Kills Nine :

“The police said they were investigating the cause of the collapse on Sunday at the Sasago Tunnel — a three-mile passage near the city of Otsuki and about 50 miles west of Tokyo — and for evidence of negligence by the company that operates the highway.
News reports said investigators believed that supports in the ceiling of the 35-year-old tunnel might have grown brittle, allowing hundreds of the slabs to fall onto passing vehicles. Each slab weighed 1.2 tons, officials said.”