Cyber attacks targeting internet infrastructure provider Dyn disrupted service on major sites such as Twitter and Spotify on Friday, mainly affecting users on the U.S. East Coast, according to Reuters.
It was not immediately clear who was responsible for the attacks. Officials told Reuters that the U.S. Department of Homeland Security and the Federal Bureau of Investigation were both investigating.
Dyn said it had resolved one attack, which disrupted operations for about two hours, but disclosed a second attack a few hours later that was causing further disruptions.
In addition to the social network Twitter and music-streamer Spotify, discussion site Reddit, hospitality booking service Airbnb and The Verge news site were among companies whose services were disrupted on Friday.
Amazon.com Inc's web services division, one of the world's biggest cloud computing companies, also reported a related outage, which it said was resolved early Friday afternoon, according to Reuters.
Dyn is a Manchester, New Hampshire-based provider of services for managing domain name servers. Its customers include Pfizer, Visa, Netflix and Twitter, SoundCloud and BT.
Dyn said it was still trying to determine how the attack led to the outage but that its first priority was restoring service.
The disruptions come at a time of unprecedented fears about the cyber threat in the United States, where hackers have breached political organizations and election agencies.
Most recently, there were attempts to hack mobile phones used by Democratic Party officials.
The FBI is already investigating a previous hacking of Democratic National Committee (DNC) computers, which was followed by 20,000 emails being published and showing a DNC favorable to Hillary Clinton over Bernie Sanders.
Clinton said during a recent presidential debate that there was "no doubt" Russia has sponsored hacks against "all kinds of organizations in our country" and mentioned Russian President Vladimir Putin by name.
(Arutz Sheva’s North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Arutz Sheva articles, however, is Israeli time.)