The Japanese motor major Honda Motor Company in Japan has put an estimated 2.2 million customers in the U.S. on a security breach alert after a database containing information on the owners and their cars was hacked, according to reports.

The compromised list contained names, login names, e-mail addresses and 17-character Vehicle Identification Number - an automotive industry standard - that was used to send welcome e-mail messages to customers that had registered for an Owner Link account, media reports added.

Another 2.7 million My Acura account users also were affected by the breach to a limited degree. Honda has said that list contained only e-mail addresses. Acura is Honda's luxury vehicle brand.

According to Honda's notification e-mail to affected customers, the list was managed by an unnamed vendor. On a Web site addressing customers, Honda said it would be difficult for a victim's identity to be stolen based on the information that had been leaked.

However, it warned that customers ought to be wary of unsolicited e-mail messages requesting for personal information such as Social Security numbers or credit card numbers.

Honda communicated with affected customers via e-mail. American Honda Motor Co., Inc. recently became aware of unauthorized access to an e-mail list used by a vendor to create a welcome e-mail to customers who have an Owner Link or My Acura vehicle account, said the message.

American Honda Motor Co., Inc. will not send you e-mails asking for your credit card number, Social Security number or other personal information, the company wrote. If ever asked for this information, you can be confident it is not from us.