A worker at Japan's Nuclear Regulation Authority (NRA) lost his work phone with sensitive information during a personal visit to China, Japanese media report. The phone held confidential contacts of staff involved in nuclear security work. The NRA could not confirm if the data was leaked. The loss happened on November 3 during a security check at Shanghai airport. The employee noticed the phone missing three days later and failed to recover it. The NRA provides smartphones to employees to respond quickly in emergencies. This comes as Japan tries to restart its atomic energy program, which stalled after the 2011 Fukushima nuclear disaster. The NRA was created to ensure nuclear safety and oversee reactor restarts. The lost phone belonged to a department that protects nuclear materials from theft and terrorism, according to Kyodo News. The NRA reported the incident to the Personal Information Protection Commission and warned staff not to take work phones abroad. This is not the first security slip-up. In 2023, an employee at Japan's largest nuclear plant, Kashiwazaki-Kariwa, lost documents after placing them on a car roof. Last November, another employee mishandled confidential documents by copying and locking them in a desk. Recently, Chubu Electric Power admitted to using cherry-picked data in safety checks, leading NRA to suspend reactor restart reviews citing "fabrication of critical inspection data," Reuters reported.