The hacker, who has been named only as P4x, launched repeated DDoS attacks

Such attacks overwhelm a target's servers bringing down their websites

P4x said he carried out the attacks after he himself was targeted by DPK hackers

Experts first believed the disruption was caused by Western powers in response to a recent spate of North Korean missile tests 

An American hacker 'in his pyjamas' has taken down North Korea's internet in revenge for a cyber attack carried out against him by Pyongyang.

The hacker, who has been named only as P4x, launched repeated 'distributed denial of service' (DDoS) attacks against the communist state, crippling the country's few government-operated public-access websites and slowing email traffic.