North Korean Radio Broadcasts Random Numbers — Is Country Sending Coded Messages to Its Spies In The South?

North Korea’s state radio has been intermittently broadcasting a string of random numbers. South Korea suspects these numbers could be coded messages that are being sent to the North’s operatives operating in the region.

North Korea appears to have resumed broadcast of encrypted messages in the form of a string of numbers that appear to be random. A South Korean government official insists the North used to transmit messages in similar manner a long time ago. The messages were apparently meant for North Korean spies operating in South Korea.

According to South Korea’s news agency, Yonhap News, North Korea operates a propaganda-spewing radio station. Called Radio Pyongyang, the station aired multiple short broadcasts last week, each lasting anywhere between 2 and 14 minutes. During the first broadcast that took place on June 24, a female reader read numbers for 2 minutes. The one on Friday was significantly longer and lasted for about 14 minutes. The person doing the news reading appeared to be reading out numbers that seemed to be page numbers of a book, claimed Seoul’s Unification Ministry and National Intelligence Service.

The agencies had a copy of those cryptic comments, which include phrases such as “No. 35 on Page 459” and “No. 55 on Page 913.” The announcer in the North Korean broadcasts described the numbers as “review assignments in physics (under the curriculum of) the remote educational university for the geological expedition members across the country” or “practice assignments in mathematic lessons (under the curriculum) of the remote educational university for expedition members of team No. 27,” reported Yahoo.

The broadcasts began early in the morning. Seoul claims it picked up such broadcasts for the first time in 16 years. It is not clear why North Korea has resumed broadcasting seemingly random string of numbers, but it used to send out such messages regularly. The country ceased to send such messages after the first inter-Korean summit in June, 2000.


Captured North Korean spies had revealed that Pyongyang sent such numbers via shortwave radio to give missions to agents dispatched to South Korea during the Cold War. Such broadcasts were eventually retired after the internet became the preferred medium to communicate with covert operatives.

Why has North Korea allegedly resumed sending supposedly encrypted messages over the radio? Relations between the two Koreas have been steadily deteriorating over the past few months. After the countries shuttered the only industrial complex they jointly operated, South Korea has become increasingly wary of the North.

Moreover, North Korea has been pursuing its nuclear ambitions with utter indifference to mounting international sanctions, reported the Guardian. The country recently fired three ballistic missiles into the sea as an apparent show of military might. In the recent past, it’s alleged an earth observation satellite was believed to be a long-range ballistic missile test in disguise.

Interestingly, a few experts on the region strongly believe North Korea hasn’t resumed sending encrypted messages over the radio. It is quite likely the country might be attempting to wage a psychological warfare with the South. North Korea might be trying to imply that it has stepped up its espionage activities in South Korea. Experts point out the many flaws in the old-fashioned “number stations” broadcasts. The encryption techniques are too cumbersome for everybody involved, they are easy to crack, and very hard to reset if compromised.

Besides, North Korea has already perfected the current espionage communication technique referred to as steganography, which involves hiding messages within audio and video files.

[Photo by Chung Sung-Jun/Getty Images]