The London Stock Exchange suffered its biggest halt in trading for eight yesterday after the electronic system that traders use to buy stocks and shares crashed.

The computer outage meant that all trading had to be suspended. The reason for the 'crash' is still uncertain but some analysts are putting it down to a surge in trading.

The surge was triggered because of an increase in trading brought on by the introduction of 'deep fee' cuts by the LSE.

The computers went down just after 7.00 yesterday morning and didn't get going again till 15.00 – 30 minutes before trading was due to finish.

The computer outage also came after what could well have been the biggest trading day in the year, with the announcement that the US government has alleviated money woes by buying mortgage lenders Fannie Mae and Freddie Mac.

High-profile lesson

Speaking about yesterday's computer outage, Bob Dowson, Operations Director of Site Confidence, the UK's leading load testing and website monitoring company, said: "Even in these economically uncertain times when budgets are constrained, all companies – even those as established as the LSE – need to focus time and resources on repairing faults and maintaining availability to their website.

"I imagine that rival trading platforms will have benefited all day from the LSE outage. Hopefully this incident will serve as a rather high-profile lesson for other organisations."

The LSE is due to upgrade its trading system soon, migrating Italian equities to its trading platform TradElect this month.