At the event, which starts on 28 April, Blunkett will advise delegates that computer and communications systems will suffer a "complete meltdown" unless channels that can respond to and mitigate attacks are used properly. He is also expected to criticise the way the UK responds to threats.
Blunkett will warn of advanced infiltration techniques and sophisticated criminals who are looking to disrupt the Olympics and the UK economy as a whole.
"The threat by organised criminals engaging in sophisticated fraud is just as great as the danger from those seeking to damage the economic, commercial and political life of the country," he will say, according to a copy of the speech seen by vnunet.com.
"Such criminals could target a whole range of Olympics visitor requirements, from ticketing, transportation and the crucial area of hotel and other bookings, which would severely disrupt, or even wipe out, accommodation reservations.
"A sophisticated attack of this sort would be economically and commercially devastating, but the ability to block it exists and could demonstrate that Britain is the best and safest place for e-commerce in the world."
Blunkett will continue his speech with the warning that the UK appears to be ill-equipped to handle such attacks.
"There still appears to be a woeful level of awareness of the threat of cyber attack, organised crime and the level of fraud, covering government, business and individual consumers and users of the internet. Awareness of the processes and technology to protect from this - and worse - is very low," he will say.
Blunkett will recommend a co-ordinated approach to cyber crime prevention and detection, and a partnership approach that takes in organisations of all kinds.
"Compare this with what is happening in the US, where $100m [£68m] in the last six months was spent on combating attacks not just on military centres, but water supply, electricity installations and other major utilities," he will explain.
"The level of complacency from our own utilities is breathtaking. That is why urgent and decisive leadership from government in partnership with business and those with security expertise is urgently needed."
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