TWELVE people were killed and dozens injured in a bomb blast in York – a sick email hoax told shocked office workers.

At least ten employees at City of York Council were targeted yesterday by the malicious spam, which claimed a “dirty bomb” had gone off near the market.

Internet security experts are investigating the email, which has been spread around the world, but is automatically tailored to the recipient’s location.

One of the recipients, at City of York Council, said they quickly realised it was fake.

The email directs the recipient to a fake Reuters news page, containing a false news report and video file containing a virus. The criminals responsible use internet locator devices to identify where the recipient is, and change the name of the town or city accordingly, although the rest of the message contains several grammatical errors.

York council staff received a message stating: “At least 12 people have been killed and more than 40 wounded in a bomb blast near market in York.

“Authorities suggested that explosion was caused by ‘dirty’ bomb. Police said the bomb was detonated from close by using electric cables.

“It was awful,” said the eyewitness about blast that he heard from his shop.

“It made the floor shake. So many people were running.”

“Until now there has been no claim of responsibility.” The email has been recorded in other cities, including Amsterdam. It typically arrives with one of the subject headings: “Take Care”; “Are you and your friends in good health?”; or “Why did it happen in your city?”.

One City of York Council worker, who asked not to be named, said they had realised the email was a hoax, but feared others would have been upset by it.

The virus hoax has been reported on computer software websites in recent days, but had not been recorded in York until now.

Graham Cluley, of internet security experts Sophos, told industry media: “You’ll notice that the hackers did not do a brilliant job in their wording – which might ring alarm bells in some people.

“But I wonder how many others would be blind to such a clue, and just click on the video regardless?”

Nigel Ayre, the council’s information management and e-government champion, said: “It is unfortunate that every new form of technology develops new criminal activity. As we quite rightly seek to increase the numbers in society who are computer literate and ever increase the range of services that are provided electronically, it is essential we continue to increase awareness of the dangers that lurk.

“Even for those who consider themselves computer literate, the threats are becoming more sophisticated and harder to spot. It is essential to be vigilant when it comes to emails.”