AUTHORS NOTE: The content of these coded messages may have no content at all and are being used to make S.Korea think spies have infiltrated their ranks.
SEOUL, Dec. 30 (Yonhap) -- North Korea's state radio station resumed broadcasting mysterious numbers Friday in what could be some kind of coded message to its agents operating in South Korea.
Radio Pyongyang, the North's state-run radio station, started broadcasting messages at 1:15 a.m. (Seoul time), calling out a series of pages and numbers, such as No. 69 on Page 894, before repeating them one more time.
The radio announcer said, "(I'm giving) review works in math lessons of the remote education university for No. 27 expedition agents." The content was the same as those transmitted in the early hours of Dec. 16.
Since June 24, 20 of such encrypted numbers broadcasts have been discovered, with the latest one broadcast Sunday.
Broadcasts of mysterious numbers are considered a kind of book cipher that was often used by North Korea to give missions to spies operating in South Korea during the Cold War era. Spies could decode numbers to get orders by using a reference book, although many intelligence officials believe this form of sending orders to be totally outdated.
Many have said the broadcasts may be some sort of psychological strategy aimed at sparking internal confusion within South Korea.
Pyongyang had initially suspended such broadcasts in 2000, when the two Koreas held their first historic summit.