https://www.bbc.com/news/live/cv1j309d4g98t?post=asset%3Add4379da-d38f-4795-ba9e-137ffe7b9e4f#post

無閉塞運転！＞＜；
"""
According to Puente, a computer failure led to the initial halt of six moving trains, including the two trains that subsequently collided.

"In the event of a system failure, the control centre takes over," Puente says, adding it was the control centre which decided to allow the trains to move again, without any speed restrictions.

That decision, Puente said, was made "under inexplicable circumstances".
"""