Sellafield, the UK's most dangerous nuclear plant, has been hacked by Russia and China, it has been claimed.

The plant in Cumbria has come under cyber attack by groups linked to the two nations.

It is a large multi-function nuclear site close to Seascale on the coast.

Sellafield is the most hazardous location in the whole of the UK.

The plant in Cumbria has come under cyber attack by groups linked to Russia and China

The data breach has been covered up by senior officials, The Guardian has reported.

Authorities are uncertain exactly when the plant's IT systems were first compromised, but breaches were first detected in 2015.

Experts noticed that software that be used to attack systems - known as sleeper malware - had been embedded into computer networks at Sellafield.

It is not clear if the software has been removed, raising concerns about the leakage of sensitive and important information.

Breaches were first detected in 2015

Sellafield used to be a power station but now processes nuclear waste from across Britain.