An employee at an All Nippon Airways subsidiary was arrested Saturday on suspicion of stealing three of the airline's laptop computers containing personal data on 5,300 customers, police said.
ANA had announced Friday that the laptop computers were missing from its Tokyo branch in Minato Ward.
Shigeru Takizawa, 32, of ANA Communications Co. allegedly stole the three computers from the branch's corporate sales section at around 2 a.m. Thursday, according to the police.
He has admitted to the allegations and apologized, they said.
According to ANA, the computers require passwords both when activating the machine and when accessing the data.
However, Takizawa reportedly did not know the passwords and there was no indication anyone had even tried to access the information on the computers.
Police said it is unlikely the data, which included customers' names, birth dates, home addresses, jobs and flight records, has been leaked.
An ANA employee discovered that the three computers were missing from the corporate sales section after arriving at work Thursday morning, ANA said.
The airline said an IC card is required to enter the office building. Police checked the entry and departure records of every person who accessed the floor where the computers were kept and narrowed the search down to Takizawa.
ANA's in-house regulations have since April banned employees from saving customer information on laptop computers and required them to store machines in locked personal lockers.