Seven people were killed when a bus carrying dozens of holidaymakers to Tokyo Disneyland crashed on a highway and was sliced in two by a steel wall.

Police said 38 other passengers and the 43-year-old driver were injured, 13 of them seriously, in the accident in Gunma, north of Tokyo.

The bus crashed into a roadside wall, with steel wall panels slicing its body in half lengthways.

Six of the dead were women in their 20s and the seventh was a man in his 40s or 50s. Police were having difficulty identifying the mangled bodies.

The crash came as Japan headed into the "Golden Week" holidays.