New Year's Eve: Extra armed officers on patrol to protect London from Isis-inspired terror attack

Extra armed police will be patrolling London tonight as security forces implement “precautionary” measures to protect millions of people seeing in the New Year.

The capital is one of several on alert in Europe after Austrian authorities said a “friendly” intelligence service warned numerous cities of a possible shooting or bomb attack by terrorists over the festive period.

Police in Vienna did not name any specific cities and Scotland Yard insisted its strategy was not a response to “specific intelligence.

At least seven terror plots have been thwarted by British security services in the past year and David Cameron said agencies had been “preparing for” attacks like those orchestrated by Isis in France.

The Metropolitan Police would not confirm a report by the Telegraph that every firearms officer in London would be on duty tonight after New Year leave for more than 2,000 personnel were cancelled.

A spokesperson told The Independent she would not discuss officer numbers but the force had earlier said around 3,000 officers would be stationed across central London.

The Home Office has put an extra £34 million into a “national uplift in armed policing capability and capacity” to respond to a Paris-style attack but said it was up to the leaders of individual forces to determine the number of firearms officers to deploy.

"New Year's Eve is a major celebration in the diary and the Met has been working with colleagues to ensure celebrations run smoothly and the event is safe and enjoyable for everyone who attends,” Superintendent Jo Edwards said.

"Our policing plan remains under constant review and the public can expect to see additional police officers in central London, which includes an increased number of firearms officers. Our plans are purely precautionary and not as a result of any specific intelligence.“

The Met is working with the Mayor’s office, British Transport Police (BTP) and local authorities to manage crowds attending the sold-out New Year’s Eve fireworks.

Entry to viewing areas along the Thames will only be open to people holding tickets to the event, which is raising money for Unicef

Boris Johnson said he had seen nothing to suggest a specific terror threat to London and urged people to “get out there and soak up” the celebrations.

All transport will be free in London between quarter to midnight at 4.30am and the Tube will be running all night to get people home, although some central stations will be closed or made exit-only for crowd control.

Rolling road closures will be starting at 2pm for both vehicles and pedestrians, who will be searched entering the fireworks viewing zone.

Superintendent Andy Morgan, silver commander for British Transport Police, said extra officers were being deployed at stations and that armed patrols were being extended.

“We would encourage everyone to enjoy their evening and to travel home safely, making sure you have your travel arrangements in place and know when your last train home is,” he added.

Additional reporting by PA