Japan's major telecom carriers are offering users the capability to register and check whether a person is safe after a massive earthquake hit central Japan.

Four major carriers -- NTT Docomo, KDDI, Softbank and Rakuten Mobile -- are now operating a disaster message board. Users can post their safety status in text messages to the Internet. The information can be checked from smartphones, other mobile phones, and PCs.

Fixed-line carriers NTT East and NTT West are also offering a disaster emergency voice message dial service. Users should dial 171 from mobile or conventional phones. Messages are recorded when their phone numbers are input. Messages can be played back when dialing 171 and inputting the phone number.

The two carriers also started an online service that allows users to record and check messages via the Internet. The website is https://www.web171.jp.