Hundreds of websites were knocked offline after an outage at web infrastructure service Cloudflare.

The outage hit websites like messaging platform Discord and e-commerce service Shopify.

The National Rail Enquiries website was also down and could have been affected, but it was already experiencing a surge in traffic because of today’s rail strikes which could have caused connection issues.

Visitors to that site and others saw a message saying: “500 Internal Server Error”, according to web monitoring service Down Detector and internet users.

Cloudflare, a US company, says the issue is now resolved.

In a series of Twitter posts it confirmed it was aware of the “current service issues” and said its team was “working to resolve (it) as quickly as possible”.

The US company is a content delivery service and its technology helps to power many of the major websites used by internet users every day.