The incident occurred on the Tokyo-bound lanes inside the Sasago tunnel on the Chuo Expressway at around 8am local time (10am AEDT) on Sunday, public broadcaster NHK and Jiji Press said.

An NHK reporter said the tunnel started to disintegrate when he was driving through it on his way to Tokyo.

‘‘I managed to drive through the tunnel but vehicles nearby appeared to have been trapped,’’ he reported.

‘‘Black smoke was coming and there seemed to be a fire inside the tunnel.’’

Police said an unknown number of vehicles were ablaze inside the tunnel.

‘‘We don’t know exactly how many vehicles are on fire,’’ an official at the local expressway traffic police unit told AFP by telephone.

A woman was taken to hospital by ambulance after she came out of the tunnel, the spokesman said.

‘‘We have limited information on the accident at the moment but smoke is said to be coming out from the tunnel as an unspecified number of vehicles were burning,’’ the official said.

More to come

AFP