Two waves of online attacks hit multiple major websites today, affecting many users across the nation. They have made it impossible for some businesses to use their websites. Users will typically see a message that the server is not available.

The issues started this morning when someone, or a group of people, flooded internet performance company Dyn with large amounts of fake traffic in an attempt to overwhelm the system and take it offline.

It is unknown who is behind the cyber attacks. The U.S. Department of Homeland Security is monitoring the situation.

If your website has been affected, you must wait it out until the attacks end.