Police have rejected suggestions that a communication breakdown led to the Prince of Wales and Duchess of Cornwall being caught up in student protests.
It has been reported that police guarding the couple were using a different radio frequency to those policing the London demonstrations.
Scotland Yard insisted the two teams were in contact and may have used mobile phones or e-mail.
A major inquiry into the student disorder of recent weeks has begun.
'Intent on violence'The prince's and the Duchess of Cornwall's car was daubed with paint and had a window smashed during tuition fee protests on Thursday.
The royal couple were being escorted by outriders and Royalty Protection Officers to a theatre in central London when their car was attacked.
A police spokesman said the route along Regent Street had been checked minutes before the incident and was deemed to be safe.
Ex-home secretary Alan Johnson said he was "amazed" by newspaper claims that teams were not fully in touch because protection officers had been so "meticulous" whilst protecting him.
And former Met firearms officer Roger Gray said it may have been more confusing if officers shared the same radio frequency, because there was a risk they could start interrupting each other.
Clarence House, meanwhile, has refused to comment on reports the Duchess was poked with a stick.
The police blame a fast-moving situation on the ground for the security breach, as protesters had been roaming through the West End in small groups, away from the larger protest in Parliament Square.
There were violent clashes on Thursday as MPs voted to allow university tuition fees to rise to up to £9,000 per year in England.
Prime Minister David Cameron condemned the disturbances and Scotland Yard said it had launched a "major criminal investigation" into student disorder between 10 November and 10 December. BBC News
