North broadcasts coded message North Korea broadcasted indecipherable five-digit number segments during a radio segment on Friday, a Cold War-era espionage method intended to relay information to agents in the field, according to a North Korea intelligence source.



The source exclusively told the JoongAng Ilbo that the North’s propaganda radio station Pyongyang Radio Station aired a 12-minute segment in which a female announcer read five-digit numbers for 12 minutes, the first such broadcast in 16 years.



The source said the authorities were poring over the North’s intentions in making such a broadcast. Not since 2000, when the first inter-Korea summit was held in Pyongyang, has the North aired such a coded-message on shortwave radio broadcast, known as the “numbers stations.”



The coded radio broadcast began at 12:45 a.m. on Friday when an unnamed female announcer began the segment by saying, “From now on, I will give review work for the subject of mathematics under the curriculum of a remote education university for exploration agents of the 27th bureau.”



The news reader continued by saying, “On page 459, question number 35, on page 913, question number 55, on page 135, question number 86, on page 257, question number 2,” followed by more numbers until 12:57 a.m.



South Korean intelligence was familiar with the North’s use of such old-fashioned communication at the height of the Cold War era, when the two Koreas were also at the apex of inter-Korea tension.



But the North stopped airing such radio encrypted messages in 2000 because of the summit between then-North Korean leader Kim Jong-il and former South Korean President Kim Dae-jung in June that year.



South Korean intelligence is reportedly scrambling to find out why Pyongyang resumed this type of communication 16 years after its last such message, particularly in the digital age when it could have simply given out orders via the internet.



The revelation has put the government on high alert over possible strikes against facilities in the South by agents sent by the North.



The timing of the broadcast also alarmed authorities as it was aired just one week after a decision by Seoul to deploy the U.S.-made missile defense system known as the Terminal High Altitude Area Defense (Thaad) system, which has drawn sharp protest from Pyongyang and Beijing.



BY LEE YOUNG-JONG, KANG JIN-KYU [kang.jinkyu@joongang.co.kr]