Here's why there were so many police patrolling in Leeds city centre

Project Servator is a nationally developed set of police tactics intended to disrupt a range of criminality and counter terrorism through unpredictable and highly visible police patrols.

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A trial began at the Trinity Leeds shopping centre yesterday, with specially-trained officers speaking to retailers and residents.

Those officers have each been trained in how to to spot tell-tale signs that a person may be carrying out 'hostile reconnaissance' or engaging in other criminal activity.

Hostile reconnaissance is the information gathering a criminal does when planning to commit a criminal act, including terrorist attacks.

As well as speaking with normal site users, officers out on patrol will engage with anyone they suspect may be in the area for criminal reasons.

Assistant Chief Constable Russ Foster, of West Yorkshire Police, said: “Project Servator is based on the very latest research designed to deter, detect and disrupt criminality and counter terrorism, whilst encouraging residents to spot and report suspicious behaviour to us.

“We have been working for many months to launch this trial in West Yorkshire and will be evaluating its results in terms of the intelligence it generates and the investigations which develop from that information.”

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Project Servator involves officers in uniform and plain clothes patrolling busy areas, including city centres and tourist hotspots, at unpredictable times.

Designed by experts at the Centre for the Protection of National Infrastructure, it was first launched by the City of London Police in 2014.

The tactics are based on in-depth research into the psychology of criminality to help authorities create situations in which criminals find it hard to operate.

Several other police forces are now using Project Servator to deter and detect a range of crime form theft to potential terror-related offences.

Mr Foster said: "The launch of this Leeds-based trial means residents will see more high visibility patrols, including armed patrols, in places where people gather in the city..

“This is nothing to be alarmed about and we would encourage shoppers and residents to speak with our teams who will be carrying Project Servator leaflets and signage.

“We would ask residents to be vigilant and to approach our officers if they see anything suspicious which doesn’t look and feel right to them.”

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West Yorkshire Police and Crime Commissioner Mark Burns-Williamson said he fully supported Project Servator and its emphasis on evidence-based policing, which will ultimately help to keep people safe and feeling safe.

“It is crucial that we rely on the latest research to inform our tactics in disrupting criminal activity and counter terrorism in all its forms," he said.

“Its purpose absolutely reflects the priorities I have recently outlined in my refreshed Police and Crime Plan, particularly in meeting our strategic policing requirements, as set out in legislation.

“Likewise, I continue to oversee the response to identifying and preventing major threats to our communities and this project is a key component of the approach in helping to reassure the public of West Yorkshire.”