People who were unsuccessful in the Olympic ticket ballot have been able to buy remaining tickets for London 2012 on a first-come, first-served basis since 6am this morning.

Website users reported that the website had crashed. But organisers say the website is working and that some people are just being stopped from entering the site because of the high demand.

Many visitors to the site have been greeted by a message reading: “We are experiencing high demand.

“You will be automatically directed to the page requested as soon as it becomes available. Thank you for your patience.”

But organisers said this was not a technical problem and compared the situation to a tube station holding trains back before the station because it is experiencing a high level of traffic.

A London 2012 spokeswoman said: “The system is working, it has not crashed. Due to high demand some people are being held outside the system.

“For those in the system it is working and transactions are going through, but we are having to hold some people back from going through the site due to high demand.”

The 2.3 million tickets are on sale for 10 days. They include tickets for 310 sessions, 44 of which are medal events including archery, basketball, fencing, judo, synchronised swimming and table tennis.