The death toll in Japan's tunnel collapse rose to nine on Monday.<br/> <br />Two people are also seriously injured when 110 metres long section of the tunnel's concrete ceiling panels fell onto cars.<br/> <br />Surveillance camera shows rescuers working inside the tunnel, while crushed cars get towed away.<br/> <br />An official from the highway operator said metal rods used to secure the concrete panels may have become loose.<br/> <br />(SOUNDBITE) (Japanese) NEXCO OTSUKI SAFETY SERVICE CENTER CHIEF, MOTOHIRO TAKAMISAWA, SAYING:<br/> <br />"At this moment we're presuming that the top anchor bolts have come loose."<br/> <br />NHK reported, the ceiling panels had not been repaired or reinforced since they were built in 1977, but they passed safety checks in September.<br/> <br />Japanese media reported that the authorities have ordered highway companies with similar concrete panels to have emergency inspections.
