A massive online attack took place on Friday. The attack block access for the majority of the most visited websites. Some of the inaccessible websites were Twitter, PayPal, Spotify, Reddit, Netflix, Tumbler and Amazon.

The massive online attack was taken against Dyn, a company based in Hampshire that routes and monitors internet traffic. The attack which was identified to be a distributed denial of service attack (DDoS) started 7:10 a.m. ET and lasted for hours. It was not until 6:17 p.m. ET that the problem was resolved.

DDoS uses a very smart attack that servers are flooded with a large amount of counterfeit requests for information that the server itself is having a hard time to even respond to real requests. The attack often ends up in the site crash. Kyle York, chief strategy officer for Dyn confirmed that the attack is not new as it tends to happen repeatedly. However, he assures that they are learning through these experiences.

The massive online attack was suspected to have used Mirai, a software that uses the strategy of phishing emails through malware. It targets one computer on a specific network first and later spreads on everything that is connected to the said network or computer, The USA Today reported.

The Department of Homeland Security and the Federal Bureau of Investigation are looking at the possibilities of a non-state attack and criminal activity behind the massive online attack. The person behind the incident, however, remains unidentified.

Security researchers warned the public that what had happened on Friday is only a foretaste of how a massive online attack can rely on any internet-connected device to materialize. York, on the other hand, said that Dyn and other companies are at risk for most powerful attacks as the duration, number, types and complexity of the attack increases very fast, as per The New York Times.