The Olympic Delivery Authority (ODA) is employing almost 300 hundred people to crack down on guerrilla marketing stunts by monitoring vendors operating within 500m of Olympic sites in London.

Wearing purple uniforms, the experts in advertising and trading legislation will also be charged with checking venues on the Olympic park and have the power to tape over brand logos on-site if companies are found guilty of flouting regulations.

Businesses who break the rules, which legal experts have called the most stringent for an Olympic Games, could be taken to court, with punishments including fines up to £20,000.

A spokesman for the ODA says: “The Olympic Delivery Authority is responsible for enforcing rules laid down by Parliament, which apply only within a few hundred metres of competition venues and on a temporary basis shortly before and during the Games.

“This legislation regulates open-air trading in public places to ensure that spectators can get without delay or obstruction to the events they have paid to attend, and requires authorisation to be obtained for some types of advertising in the same areas to prevent so-called ambush marketing.  The rules apply to sponsors as much as to any other business.”

It comes as Locog has warned businesses not to use terms from a list of banned words that includes “gold”, “sponsors” and “London”. Locog will enforce these rules separately to the operation being conducted by the ODA.

Olympic chiefs have continuously stressed that without the restrictions in place sponsors including Coca-Cola, Samsung and Cadbury would not have invested in the event, which has raised almost £700m “in a very difficult environment”.

Last month, Lord Seb Coe told Marketing Week that the investment from sponsors had changed the area of East London in a way that “politicians wouldn’t have done”.

The operation by the ODA, which is being called the biggest branding operation in the UK, is launching in the same week that Olympic chiefs are invoking a blackout for non-sponsors to use athletes in their promotions. The regulation will also prevent athletes from posting tweets about their individual sponsors as part of a social media and blogging policy to ensure that they don’t accidentally break regulations. During Games Period (18 July to 15 August) athletes as well as spectators at any Olympic venue will banned from making any reference to non-sponsors on the micro-blogging site.

Despite this, Locog and Twitter are still yet to agree on how the digital guidelines will be enforced during the Games, which are being billed as the first “social Olympics”.