Since January 2024, the Kumamoto City transportation bureau has been requested to investigate causes and implement measures to prevent recurrence for numerous incidents, including accidents and major incidents. An audit conducted from April 15 to 18, 2025, identified new areas needing improvement, prompting further directives. Despite ongoing efforts, a vehicle collision at Kumamoto Castle/City Hall station on March 25, 2025, resulted in multiple injuries. The investigation by the Japan Transport Safety Board is ongoing. The guidance issued on July 18, 2025, emphasizes establishing systems for accurate on-site situation awareness, regular verification of operational status, and strengthening safety management. Specific issues include: 1) verifying driver knowledge and skills, especially regarding speed compliance; 2) ensuring proper use and carriage of safety levers; 3) reporting and recording vehicle inspections before operation. The bureau is instructed to review current procedures, implement necessary improvements, and educate relevant staff, with reports due by August 18, 2025.

On September 20, 2024, the Kumamoto City railway operator was instructed under the Railway Operation Regulations by the Kyushu Transport Bureau to ensure proper safety management following a safety audit (document No. 19). Despite these instructions and ongoing improvements, a vehicle collision occurred around 8:31 AM near Kumamoto Castle and City Hall station, injuring six passengers and one driver. This incident is considered serious as it undermines public trust in the public transportation system. The authorities emphasize the importance of recognizing the severity of the incident, conducting a prompt and thorough investigation into the cause, and implementing necessary measures to prevent recurrence. The operator is required to submit a written report detailing the cause and specific preventive actions. This constitutes administrative guidance issued by the Kyushu Transport Bureau.

Kumamoto City, operating a railway under the Railway Act, received an administrative guidance from the Kyushu Transport Bureau on January 22, 2025, based on safety audits conducted on September 20, 2024. The city submitted an interim improvement report on October 21, 2024, and has been working towards finalizing corrective actions. However, incidents continued, including a derailment on December 31, 2024, between Kumamoto Castle/City Hall and Hanabatake-cho stations, believed to be caused by gauge widening. Post-accident inspections revealed new gauge widening near the site, leading to service suspensions and impacting users. The bureau urges the city to re-assess the safety of all tracks, review current maintenance practices, investigate causes including underlying factors, and establish measures to prevent recurrence, ensuring proper safety management. The city is also required to report promptly on measures implemented. This guidance is issued by the Kyushu Transport Bureau.

Since January 2024, the Kumamoto City Transportation Bureau has experienced multiple incidents, including trains operating with open doors and signals being ignored despite showing stop indications. Despite directives from authorities to investigate causes and prevent recurrence, a derailment occurred on July 26, 2024, between Tamazaki Bridge and Nibongi stations. An audit conducted from July 10-12 and August 5-7 revealed deficiencies requiring corrective measures. The bureau must verify and improve its safety management system, focusing on safety supervisors, and address issues such as staff training, health assessments, and track maintenance. Specific issues include lack of training plans, insufficient skill and health checks, inadequate pre- and post-shift mental and physical condition checks, and failure to maintain track gauge and level standards. If the bureau fails to implement necessary improvements or if violations recur, the authorities may order business improvements based on relevant laws, citing risks to transportation safety and public interest.