About suspension of operation of some sections of the municipal subway blue line (Kami-Ooka Station-Yokohama Station)

Today, on December 4, a crack was found on the rail side between Yoshinocho Station and Bandobashi Station (up line) on the municipal subway blue line, and rail reinforcement was performed from 5:15 pm to 5:45 pm Until then, driving was suspended between Kami-Ooka Station and Yokohama Station.
We apologize for any inconvenience this may have caused to you.

1 Process
　(1) Location of occurrence
　　　Municipal Subway Blue Line between Yoshinocho Station and Bandobashi Station
　　(Driving suspension section: Kami-Ooka Station-Yokohama Station)
　(2) Progress
　　　Monday, December 4, 2023
　　　1:00 am to 4:00 am Conducted rail inspection by outsourcing
　　　　　　　　　　 (Inspection to find wounds caused by ultrasound)
　　　Analysis of test results at the contractor from 8:00 am to 11:00 am
　　　11:06 a.m. Report that there is a suspicion of wound on the rail side
　　　3:18 p.m.　 On-site confirmation (confirming scratches on the rail side)
　　　5:45 p.m.　 Reinforcement and restart operation

2 Impact
　　Approx. 14,000 employees
　　Partial suspension (Kami-Ooka Station-Yokohama Station) From 5:15 pm to 5:45 pm (30 minutes)

3 Cause
　　We are currently investigating the cause of cracks on the rail side.