Tokyo, Nov. 5 (Jiji Press)--NTT Docomo Inc. said Thursday that up to around 300,000 sets of customer information have been compromised due to unauthorized access.

The major Japanese mobile phone carrier has suspended online services, including "My docomo," which allows subscribers to check their usage, and is continuing restoration work.

The breached information includes customers' names, addresses, dates of birth and phone numbers. The company said it is still investigating whether payment information, including credit card details, has also been compromised.

NTT Docomo detected unauthorized access Wednesday and suspended My docomo and other online services early Thursday for emergency maintenance work.

It is urging customers not to provide credit card information or passwords in response to suspicious emails.

[Copyright The Jiji Press, Ltd.]