LABOUR say they are the victims a “sophisticated and large-scale cyber-attack” from an unknown source.

The party has not said which of their systems were subject to the hack, but reports suggest election and campaign tools which could contain information about voters and supporters were targeted.

The National Cyber Security Centre is investigating.

A party spokeswoman said they came under siege on Monday: “We have experienced a sophisticated and large-scale cyber-attack on Labour digital platforms.

“We took swift action and these attempts failed due to our robust security systems. The integrity of all our platforms was maintained and we are confident that no data breach occurred.

“Our security procedures have slowed down some of our campaign activities, but these were restored this morning and we are back up to full speed. We have reported the matter to the National Cyber Security Centre.”

It’s thought Labour were targeted by a distributed denial of service (DDoS) attack, where a server, service or network is overwhelmed with requests.