Image copyright AP Image caption The move follows recent terror attacks in Brussels and in Paris last year

One million people who work in crowded places in the UK are to be trained over the next 12 months in how to deal with a possible terrorist attack.

The plan, to be announced by the National Police Chiefs Council, will see staff pass on police terror training and advice to colleagues.

The initiative will extend an existing scheme, which currently sees police train around 100,000 workers a year.

Police said they need "everyone to play a part in keeping the public alert".

Det Ch Supt Scott Wilson, the national counter-terrorism co-ordinator, will announce an extension to Project Griffin to allow existing trainers at companies to pass on police training and advice to colleagues.

Public limited companies based in busy city centres - as well as those in the entertainment, sports and retail sectors - will be targeted.

"We need everyone to play a part in keeping the public alert, not alarmed," Det Ch Supt Wilson added.

'Local knowledge'

Project Griffin was initially set up by the City of London and Metropolitan police forces in 2004 to advise and train managers and security officers of large organisations on how to deal with security and counter-terrorism issues - it has since been rolled out to other forces across the UK.

"Police can help explain what the threats and risks to different sectors are, but companies are better placed to explain to staff exactly what action they can take to enhance their security and how to respond if the worst happens," Det Ch Supt Wilson said.

He added: "Individual organisations have vital protective security information such as building layouts, security equipment and safety procedures. They have the local knowledge that could be vital to keeping staff and the public safe."

BBC security correspondent Frank Gardner said the issue of preparing for a possible terror attack had been "troubling the police and intelligence agencies ever since the marauding terrorist attacks in Mumbai in 2008".

And in the wake of the recent attacks in Brussels and Paris, efforts to prepare workers in busy areas will now be "massively stepped up" to brief one million staff in the next 12 months, our correspondent said.

Terror attacks in Mumbai in 2008 killed 174 people, while attacks by gunmen and suicide bombers left 130 people dead in Paris in November last year.

Last month, bomb attacks at Brussels airport and a metro station killed 32 people.

"The move comes amid an increase in the number of trained police firearms officers to cope with the possibility that criminals inspired by the so-called Islamic State could open fire in a public place using automatic weapons smuggled in from mainland Europe," added our correspondent.