The extraordinary steps were taken as police in Manchester revealed it is 'very clear' suicide bomber Salman Abedi was part of a terror 'network' and an off-duty woman police officer was among his 22 victims.Soldiers in camouflage combat fatigues carrying the SA-80 rifles usually only fired in war zones patrolled beside Metropolitan Police officers through the streets of Whitehall this afternoon.It is the first time such a step has been taken since Tony Blair sent tanks to guard Heathrow Airport in 2003 and will be the first time most Britons have ever witnessed uniformed troops on their streets.
Metropolitan Police Commissioner Cressida Dick said: 'The military are here and a number of locations in London in order to allow us, the police, to put more armed officers on the streets to support the public, and to protect the public and to protect events.'Ms Dick said there were 'clearly a number of unknowns' since the attack on Monday and security services needed to get 'a better understanding' of the situation before the threat level could be reduced.
She added: 'We are immensely grateful to our military colleagues.
But the Met said the incident was not terror-related.
In the City, Paternoster Square, not far from St Paul's was closed by police investigating reports of a suspicious package.
This will free up armed officers to carry out patrols'.