About suspension of operation of some sections of municipal Subway Blue Line (Kami-Ooka Station-Yokohama Station)

On December 4th, a crack was found on the rail side between Yoshinocho Station and Bandobashi Station (up line) of the Municipal Subway Blue Line. Until then, driving was suspended between Kami-Ooka Station and Yokohama Station.
We apologize for any inconvenience this may have caused to you.

1 Background
　(1) Location of occurrence
　　　Municipal Subway Blue Line Between Yoshinocho Station and Bandobashi Station
　　(Transferred section: Kami-Ooka Station to Yokohama Station)
　(2) Progress
　　　Monday, December 4, 2023
　　　From 1:00 a.m. to 4:00 a.m. Implementation of rail inspection by outsourcing
　　　　　　　　　　 (Inspection to find wounds caused by ultrasound)
　　　8:00 am to 11:00 a.m. to 11:00 am Test results analysis at the contractor
　　　11:06 a.m. Report of suspected wounds on the rail side
　　　3:18 p.m.　 On-site confirmation (checking the wound on the rail side)
　　　5:45 p.m.　 Reinforcement and resumed operation

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

3 Causes
　　The cause of cracks on the rail side is currently under investigation.