Cyber attack disrupts internet service across US, Europe

United States officials are investigating multiple attacks that caused widespread online disruption on both sides of the Atlantic on Friday.

The incident took offline some of the most popular sites on the web, including Netflix, Twitter, Spotify, Reddit, CNN, PayPal, Pinterest and Fox News, as well as newspapers including the Guardian, the New York Times and the Wall Street Journal.

The Department of Homeland Security has begun an investigation into the DDoS (distributed denial-of-service) attack, the Guardian reports.

The attacks seemed to have been focused on Dyn, one of the companies which manages website domains and routes internet traffic.

Amazon's web services division, the world's biggest cloud computing company, also reported an outage that lasted several hours on Friday morning.

Doug Madory, director of internet analysis at Dyn, said he was not sure if the outages at Dyn and Amazon were connected.

"We provide service to Amazon, but theirs is a complex network so it is hard to be definitive about causality," he said.

Dyn said it first became aware of the attack shortly after 7am ET on Friday. "We began monitoring and mitigating a DDoS [distributed denial-of-service] attack against our Dyn Managed DNS infrastructure," the company said on its website.

The company sent out updates throughout the day, confirming a second attack at about noon and a third just after 4 p.m.

Analysts say that the DDoS attacks are also becoming more common.

The firm said it was still trying to determine how the attack led to the outage. "Our first priority over the last couple of hours has been our customers and restoring their performance," said executive vice-president Scott Hilton.

The tech website Gizmodo wrote: "This new wave of attacks seems to be affecting the West Coast of the United States and Europe. It's so far unclear how the two attacks are related, but the outages are very similar.