Twenty-four people were taken to hospital on Friday morning after a police vehicle taking detainees to the prosecutor's office caused a four-car crash on an expressway in central Tokyo, police said.
The police van, carrying 16 detainees and several police officers, apparently rear-ended a line of backed-up vehicles on the expressway's Inner Circular Route at around 9 a.m., according to the police.
The vehicle, driven by a 34-year-old male senior officer with the Metropolitan Police Department, was on its way to the Tokyo District Public Prosecutor's Office.
All the injuries are reportedly minor.
In a statement, an official in charge of police detention administration said they will make all-out efforts to prevent similar accidents.
The road was closed temporarily following the accident.