Tokyo, Dec 4 (IANS/EFE): The Japanese government ordered the inspection of dozens of highway tunnels throughout the country after the ceiling of one of them collapsed and killed nine people.

The incident, which also injured three other people, took place in the Sasago tunnel, some 80 km west of Tokyo. The tunnel passed its most recent inspection in September without authorities detecting any problems or anomalies.

Dozens of cement panels or slabs weighing 1.2 tonnes each became detached from the tunnel's ceiling and fell onto three moving vehicles, one of which burst into flames. Five of the six people riding in that vehicle were killed.

The other four fatalities included a man and two elderly women, as well as the driver of a frozen food truck who managed to make a cell phone call for help from inside his crushed vehicle but died before help arrived.

The authorities said that the people riding in the two cars died as a result of the fire that followed the collapse.

At present, authorities do not know the reason the panels fell onto the roadway, but employees with the Central Nippon Expressway, which operates the highway, said that one of the bars holding the slabs up could have become loose causing a chain reaction.

After the incident, the transportation ministry ordered inspections of all national highway tunnels that have the same system of cement slabs as the Sasago tunnel, public television network NHK reported.