An advertising campaign by a firm aiming to cash in on the fear of terrorism during the London Olympic games by using images of the 7/7 attacks to sell bomb-blast window film has been banned by the advertising watchdog.

The Advertising Standards Authority described the campaign, which used an image of the bus destroyed in Tavistock Square in the 7 July 2005 bombings, as "wholly inappropriate and shocking" and likely to cause serious offence.

In its ruling the ASA said that the campaign had "exaggerated the potential threat faced by businesses due to the Olympic Games and could have caused undue fear and distress to someone who received the mailing".

The advertising regulator added that the campaign was in breach of the advertising code and banned it.

Used as part of a direct mail campaign by a company called Northgate Solar Controls that aimed to drum up orders for its anti-shatter window film, the 7/7 image was sent to about 4,400 businesses.

Northgate Solar Controls told business owners they may have already been visited by the Metropolitan police or another "government agency" to warn of a "red alert for the Olympic Games".

The campaign talked of a "very real threat" of suicide bombers entering the country more easily because of large numbers of visitors swamping ports of entry and "undetected terrorist sleeper cells" that could launch an attack affecting businesses.

Northgate Solar Controls said that it only targeted businesses in London and the home counties, where most of the Olympic activity is taking place, and that it was not scaremongering but instead wanted to "help minimise the risks in the event of an explosion by the application of bomb-blast film".

However, the business that complained to the Advertising Standards Authority about receiving the direct mail shot was based "almost 50 miles away from the nearest Olympics venue in Essex".

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