A strange and mysterious collection of numbers have been detected being broadcast over radio from North Korea and everyone is baffled as to what they could mean.

"Number 35 on page 459... number 55 on page 913," were just some of the codes read out by a female announcer over North Korea's state radio for two minutes on 24 June and 14 minutes on 15 July.

These short, cryptic messages have had the South Korean Government in a state of confusion and panic as one theory to their nature could be that they could be directives for secret agents operating in the country.

According to the Guardian, during the cold war North Korea transmitted similar numbers via shortwave radio to give missions to spies in South Korea. While these may resemble those codes, due to the rudimentary nature of the communication it's unlikely this is the case.

The article also highlighted that another explanation could be an attempt by North Korea to kick-off some psychological warfare by setting off a paranoia bomb that secret spies are actively infiltrating the country or that it may be making military moves.

North Korea has recently been testing missiles following Seoul's decision to for the US to deploy a Terminal High Altitude Area Defence (Thaad) anti-missile system.

If both of these theories sound a bit far-fetched one final explanation is offered. The announcer is understood to be describing the numbers as review assignments in physics and practice assignments in mathematics lessons for the remote educational university.

So, essentially, they could be instructions for homework for students studying outside of North Korea. It's a far more logical (and sane theory) however it does still pose a few head-scratchers like why use this medium – why not email? Perhaps some students in remote regions only have access to radio, or perhaps that's exactly what North Korea wants the South to think...