UK’s Labour Party says it has repelled a DDoS attack

The United Kingdom’s Labour Party says it has fended off a large distributed denial-of-service attack on the party’s digital platforms as it prepares for a general election.

Labour leader Jeremy Corbyn said the attack occurred on Monday, calling it “very serious,” and potentially “a sign of things to come.” There was no indication that any Labour Party data had been compromised, he said.

“The attack was actually repulsed because we have an effective, in-house-developed system by people within our party,” Corbyn told reporters Tuesday.

A DDoS attack floods servers with junk traffic in an attempt to knock them offline. It is a brute-force measure that election officials around the world will have to be mindful of as they look to keep digital platforms that inform voters online.

It was not immediately clear who was responsible for the DDoS attack. Corbyn said an investigation was ongoing and that his party had reported the attack to the UK’s national cybersecurity agency. A Labour source told BBC News the attack came from computers in Russia and Brazil, but it is easy for attackers to obfuscate their location.

“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,” a Labour spokesperson said.

The Labour Party employs Cloudflare, a popular service to guard against DDoS attacks, according to a message on the Labour website.

“As a policy, Cloudflare can’t comment on individual customers without their permission,” a Cloudflare spokesperson said.

A UK general election is set for Dec. 12 amid the country’s contentious and drawn-out departure from the European Union, commonly known as “Brexit.” The Labour Party will square off with the incumbent Conservative Party, among others.