Business owners have been asked to take a lead fighting terrorism in the heart of Islington.

The Angel Business Improvement District (BID) has set up a mobile phone messaging group where managers will be sent urgent police alerts and images of people in the area suspected of being extremists.

They are then expected to pass on the information to staff, who will be tasked with ensuring the safety of customers.

Everyone using the group is made to sign a confidentiality agreement before they can access the messages and pictures.

The Met-backed scheme, which uses instant messaging service Whatsapp, has been rolled out in response to the Paris attacks in November. It is the first of its kind in the UK.

Asked whether Islington faces a particular threat, Sgt Chris Walsh told the Gazette: “The Met’s stance is there is a ‘severe’ threat across London. It’s a case of when, not if.”

Angel BID chief executive Christine Lovett said: “We are just trying to be as safe as we can, given the threat to London.

“If the worst does happen, we want to raise the alarm very quickly and if it saves one life, it’s absolutely worth it.

“The idea is to get people looking out, and hopefully this alertness will prevent anything happening.”

So far, 25 of the area’s major employers – including Royal Bank of Scotland, Hilton Hotel and Business Design Centre – have signed up. The BID eventually wants to extend the scheme to smaller businesses and residents’ groups.

Only an allocated boss of each member company is allowed to post a warning. It is seen as a way of “cutting out” hierachies in major organisations to dish out vital information in seconds.

As well as images and police alerts, bosses can share information about people they personally see acting suspiciously.

Sgt Walsh admitted it was “quite possible” mistakes could be made.

But he added: “We will deal with that if it ever comes. There are strict protocols. I have spoken to these people, who are in positions of trust, at length. I’m confident it will only be used if something serious happens.”