Amazon EC2 is down on the East Coast and it is interrupting service to major consumer sites and platforms such as Heroku.

The service issues have led to outages at popular sites such as Foursquare, Quora, Reddit and Hootsuite. Heroku has a status page for customers about the problem. The platform relies on Amazon EC2 to serve its developer community and the associated services that use it.

For example, Flightcaster is a travel app that uses Heroku. It is down right now. The site won't come up. All it shows is a placeholder page that says an application error has occurred.

Amazon's service page shows a disruption at its Northern Virginia data center.

There is a timeline with updates about the problems. The problems appear to have started at 1:41 a.m. PDT:

We are currently investigating latency and error rates with EBS volumes and connectivity issues reaching EC2 instances in the US-EAST-1 region.

The last update occured at 6:09 AM PDT:

EBS API errors and volume latencies in the affected availability zone remain. We are continuing to work towards resolution.

This disruption is one of the more serious that Amazon has ever experienced.

George Reese is the founder of enStratus, a cloud management provider. He is one of the leading experts on cloud computing and the author of several books published by O'Reilly . In his Twitter stream he says he has never seen it this bad in an EC2 region. "@reillyusa Right now, it looks like a complete network metldown."