NHN Japan, a subsidiary of Korea's top portal operator NHN Corp., said Monday the number of users of its messenger service "LINE" has topped the 60 million mark.

LINE, launched in June 2011, is the company's free group messenger application that runs on the Android, Blackberry and iOS operating systems. Users in 230 countries use the service, according to the company.

The growth was attributed to enhanced efforts to lure more users. In August, the company launched a version that is compatible with Research in Motion phones, and it has also been holding joint promotion events with overseas mobile carriers and handset makers.

NHN Japan said it aims to increase its number of users to 100 million and make inroads in the Chinese and U.S. market by the end of the year, without disclosing its schedule for overseas expansion. (Yonhap)