TOKYO (AP) -- Police were searching the offices Tuesday of the company operating an expressway tunnel where hundreds of concrete ceiling slabs collapsed onto moving vehicles below, killing nine people.
Those killed in Sunday's accident were traveling in three vehicles in the 4.7-kilometer (3-mile) long Sasago Tunnel about 80 kilometers (50 miles) west of Tokyo. The transport ministry has ordered inspections of 49 other highway and road tunnels of similar construction around the mountainous country. The tunnel, on a highway that links the capital to central Japan, opened in 1977.
About a dozen uniformed police were shown on television entering the headquarters of Central Japan Expressway Co. early Tuesday, toting cardboard and plastic boxes.
"Yes they are searching our offices here. We will be fully cooperating with them," said Osamu Funahashi, an official at the government-owned company.
Police and the highway operator are investigating why the concrete slabs in the Sasago Tunnel collapsed. An inspection of the tunnel's roof in September found nothing amiss, according to Satoshi Noguchi, another company official.
An estimated 270 concrete slabs, each weighing 1.4 metric tons (1.54 short tons), suspended from the arched roof of the tunnel fell over a stretch of about 110 meters (120 yards), Noguchi said.
The operator was exploring the possibility that bolts holding a metal piece suspending the panels above the road had become aged, he said. The panels, measuring about 5 meters (16 feet) by 1.2 meters (4 feet), and 8 centimeters (3 inches) thick, were installed when the tunnel was constructed in 1977.
Recovery work at the tunnel was suspended Monday while the roof was being reinforced to prevent more collapses, said Jun Goto, an official at the Fire and Disaster Management Agency
Yoshihiro Seto, an officer with the Yamanashi prefectural police, said they can't rule out that there are more bodies or survivors in the tunnel, but the possibility is low. Goto said they hope to resume recovery work on Tuesday.
Two people suffered injuries in the collapse.
Associated Press writer Elaine Kurtenbach contributed to this report.
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
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